feat: comprehensive audit + Tier 3 wiring (security/correctness/features)

Multi-agent audit + fix pass covering bugs, security, dead config wiring,
and missing features. All quality gates green: build/vet/test -race/govulncheck/
golangci-lint. Frontend tests 47/47.

SECURITY & CORRECTNESS

- Scanner pipeline fail-closed: cache.go scan timeout now 503 (was goto servePkg);
  scanner.go all-scanners-fail saves ScanStatusError; CheckVulnerabilities blocks
  on missing/error result instead of allowing.
- Scanner argv corrections: govulncheck source-mode + go.mod discovery;
  npm-audit generates lockfile via npm install --package-lock-only --ignore-scripts;
  pip-audit per-extension dispatch (wheel direct / sdist extract+pyproject).
- GHSA version-range filtering implemented (was always-include); url.QueryEscape
  on package name.
- pypi SSRF closed via host allowlist on original_url; url.QueryEscape on
  rewriteURL output.
- Path traversal: cache temp file uses os.CreateTemp; smb keyToPath sanitized;
  filesystem keyToPath returns error + filepath.Abs prefix-verify.
- Goroutine leaks plugged: cache.cleanupWorker stop channel; auth.ValidationCache
  Stop() with sync.Once; ws.unregister buffered with non-blocking send.
- WebSocket double-close panic fixed via sync.Once Client.closeSend().
- Race conditions: gormstore.registryCache sync.RWMutex (was concurrent map
  panic); auth.LastUsedAt no longer mutated under RLock; analytics strict
  lock-ordering invariant (statsMu before downloadsMu).
- Auth validator fails CLOSED on transport/unknown-status errors (was returning
  true,err 'allow cache fallback').
- Credential cache hash full SHA256 (was 8-byte truncate; eliminates 2^32
  collision risk).
- filesystem.fs.used incremented after successful rename (no quota inflation
  race).
- gormstore aggregation events deleted in same tx as insert (no double-counting).
- gormstore.SavePackage uses Updates(map) so zero-value security flags
  (RequiresAuth=false) can be cleared.
- partition_manager validates partition name regex before DROP TABLE.
- vcs/git: version regex validation rejects --option-injection; checkout uses
  --detach -- separator; removed TrimPrefix(repo,'v') that corrupted vault/
  vitess/vim-go.
- WebSocket CheckOrigin allowlist (was return true; CSWSH closed); same-origin
  default + ServerConfig.AllowedOrigins.
- fiber CVE GO-2026-4543 patched (v2.52.10 -> v2.52.12).

FUNCTIONAL FEATURES

- API key DB persistence: APIKeyModel + migration 202604280002, full CRUD,
  async LastUsedAt updates with WaitGroup-tracked goroutines drained on Close.
- Admin bootstrap via GOHOARDER_BOOTSTRAP_ADMIN_KEY env var; idempotent
  (skipped when non-revoked admin already exists).
- Auth middleware factory in pkg/app: RequireAuth, RequireRole, RequirePermission,
  OptionalAuth. Mounted on proxy + read APIs when Auth.Enabled=true.
  DELETE /api/packages/* requires admin role. /health public for k8s probes.
- NFS storage backend: pkg/storage/nfs wraps filesystem with /proc/mounts
  detection (Linux), post-write fsync, read-after-write health probe.
- WebSocket real-time pipeline: pkg/events Broadcaster interface; cache + scanner
  managers emit EventPackageCached / EventPackageDownloaded / EventScanComplete;
  app.go runs 30s EventStatsUpdate ticker. Frontend has full WS client (reconnect
  with exponential backoff 1s->30s, 25s heartbeat, subscriber pattern), Pinia
  realtime store, Dashboard live indicator + activity feed + reactive stats
  override.
- TLS termination: fiber.ListenTLS when Server.TLS.Enabled.
- Pre-warming: Prewarming.Enabled flag wired (was hardcoded false); Interval,
  MaxConcurrent, TopPackages plumbed.
- NetworkConfig wired (timeouts, retry, rate-limit, circuit-breaker).
- AuthConfig.BcryptCost wired.
- Security.Scanners.Static.MaxPackageSize plumbed to cache.io.LimitReader.
- Handlers.{Go,NPM,PyPI}.Enabled gates route mounting.
- Graceful shutdown: authManager.Close drains async writes.

LINT/HYGIENE

- 80 golangci-lint issues resolved: errcheck (Close/Write/RemoveAll wrapped),
  gofmt, gosec G104/G306, govet shadow renames + fieldalignment reorders,
  staticcheck ST1000 pkg comments + QF1003 tagged switches + QF1008 embedded
  field selectors + QF1001 De Morgan's law.

BEHAVIOR CHANGES

- Scanner now fail-closed: deployments without scanner binaries
  (trivy/govulncheck/npm-audit/pip-audit/grype) BLOCK packages instead of
  serving unscanned. Add binaries or plan a future allow-on-scan-error flag.
- WS origin defaults to same-origin; cross-origin dashboards must set
  server.allowed_origins.
- Validator no longer fails open; private packages won't serve from cache when
  validation can't be performed.
- download_events retention dropped from 24h to ~5min (deleted in agg tx).
  Migration 202604280001 purges pre-upgrade events.
- DELETE /api/packages/* requires admin role when auth enabled.

NEW PACKAGES

- pkg/events  - Broadcaster interface
- pkg/storage/nfs  - NFS-aware filesystem wrapper

DEFERRED (out of scope this pass)

- Static scanner implementation (config defines AllowedLicenses/MaxPackageSize/
  BlockSuspicious but pkg/scanner/static/ does not exist).
- AuthConfig.AuditLog wiring (no audit log infra yet).
- CacheConfig.TTLOverrides passthrough (would touch cache.Config beyond
  integrator scope).

pkg/cache/cache_test.go

@@ -6,16 +6,52 @@ import (
 	"errors"
 	"io"
 	"strings"
+	"sync"
 	"testing"
 	"time"
 
 	"github.com/lukaszraczylo/gohoarder/pkg/metadata"
 	"github.com/lukaszraczylo/gohoarder/pkg/storage"
+	"github.com/lukaszraczylo/gohoarder/pkg/websocket"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/mock"
 	"github.com/stretchr/testify/require"
 )
 
+// fakeBroadcaster records BroadcastEvent calls for assertions.
+type fakeBroadcaster struct {
+	events []fakeBroadcastEvent
+	mu     sync.Mutex
+}
+
+type fakeBroadcastEvent struct {
+	Payload any
+	Type    string
+}
+
+func (f *fakeBroadcaster) BroadcastEvent(eventType string, payload any) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.events = append(f.events, fakeBroadcastEvent{Type: eventType, Payload: payload})
+}
+
+func (f *fakeBroadcaster) snapshot() []fakeBroadcastEvent {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	out := make([]fakeBroadcastEvent, len(f.events))
+	copy(out, f.events)
+	return out
+}
+
+func (f *fakeBroadcaster) typesOnly() []string {
+	snap := f.snapshot()
+	out := make([]string, len(snap))
+	for i, e := range snap {
+		out[i] = e.Type
+	}
+	return out
+}
+
 // MockStorageBackend is a mock for storage.StorageBackend
 type MockStorageBackend struct {
 	mock.Mock
@@ -194,6 +230,29 @@ func (m *MockMetadataStore) AggregateDownloadData(ctx context.Context) error {
 	return args.Error(0)
 }
 
+// API key methods are not used by the cache package; stub them out so the
+// mock continues to satisfy metadata.MetadataStore after the interface gained
+// API key persistence methods.
+func (m *MockMetadataStore) SaveAPIKey(ctx context.Context, key *metadata.APIKey) error {
+	return metadata.ErrNotImplemented
+}
+
+func (m *MockMetadataStore) GetAPIKey(ctx context.Context, id string) (*metadata.APIKey, error) {
+	return nil, metadata.ErrNotImplemented
+}
+
+func (m *MockMetadataStore) ListAPIKeys(ctx context.Context) ([]*metadata.APIKey, error) {
+	return nil, metadata.ErrNotImplemented
+}
+
+func (m *MockMetadataStore) DeleteAPIKey(ctx context.Context, id string) error {
+	return metadata.ErrNotImplemented
+}
+
+func (m *MockMetadataStore) UpdateAPIKeyLastUsed(ctx context.Context, id string, t time.Time) error {
+	return metadata.ErrNotImplemented
+}
+
 // TestNew tests cache manager creation
 func TestNew(t *testing.T) {
 	tests := []struct {
@@ -981,3 +1040,177 @@ func TestConcurrentGet(t *testing.T) {
 	// Verify at least one call was made (singleflight may deduplicate others)
 	mockMetadata.AssertCalled(t, "GetPackage", mock.Anything, "npm", "concurrent", "1.0.0")
 }
+
+// TestBroadcaster_CacheHit verifies EventPackageDownloaded fires on a
+// cache-hit serve and no other events are emitted.
+func TestBroadcaster_CacheHit(t *testing.T) {
+	mockStorage := &MockStorageBackend{}
+	mockMetadata := &MockMetadataStore{}
+
+	now := time.Now()
+	expiresAt := now.Add(24 * time.Hour)
+	pkg := &metadata.Package{
+		ID:           "test-id",
+		Registry:     "npm",
+		Name:         "react",
+		Version:      "18.2.0",
+		StorageKey:   "npm/react/18.2.0",
+		CachedAt:     now,
+		LastAccessed: now,
+		ExpiresAt:    &expiresAt,
+	}
+	mockMetadata.On("GetPackage", mock.Anything, "npm", "react", "18.2.0").Return(pkg, nil)
+	mockStorage.On("Get", mock.Anything, "npm/react/18.2.0").Return(io.NopCloser(strings.NewReader("cached data")), nil)
+	mockMetadata.On("UpdateDownloadCount", mock.Anything, "npm", "react", "18.2.0").Return(nil)
+
+	manager, err := New(mockStorage, mockMetadata, nil, nil, Config{})
+	require.NoError(t, err)
+
+	bc := &fakeBroadcaster{}
+	manager.SetBroadcaster(bc)
+
+	entry, err := manager.Get(context.Background(), "npm", "react", "18.2.0", nil)
+	require.NoError(t, err)
+	require.NotNil(t, entry)
+
+	events := bc.snapshot()
+	require.Len(t, events, 1, "expected exactly one event on cache hit")
+	assert.Equal(t, string(websocket.EventPackageDownloaded), events[0].Type)
+
+	payload, ok := events[0].Payload.(map[string]interface{})
+	require.True(t, ok, "payload should be map[string]interface{}")
+	assert.Equal(t, "npm", payload["registry"])
+	assert.Equal(t, "react", payload["name"])
+	assert.Equal(t, "18.2.0", payload["version"])
+	assert.Equal(t, true, payload["cache_hit"])
+}
+
+// TestBroadcaster_CacheMissStore verifies EventPackageCached fires on a
+// cache-miss-then-store path and EventPackageDownloaded does NOT fire
+// on that path (avoid double counting).
+func TestBroadcaster_CacheMissStore(t *testing.T) {
+	mockStorage := &MockStorageBackend{}
+	mockMetadata := &MockMetadataStore{}
+
+	mockMetadata.On("GetPackage", mock.Anything, "npm", "lodash", "4.17.21").Return(nil, errors.New("not found"))
+	mockStorage.On("GetQuota", mock.Anything).Return(&storage.QuotaInfo{Used: 100, Available: 900, Limit: 1000}, nil)
+	mockStorage.On("Put", mock.Anything, "npm/lodash/4.17.21", mock.Anything, mock.Anything).Return(nil)
+	mockMetadata.On("SavePackage", mock.Anything, mock.Anything).Return(nil)
+	mockStorage.On("Get", mock.Anything, "npm/lodash/4.17.21").Return(io.NopCloser(strings.NewReader("upstream data")), nil)
+	mockMetadata.On("UpdateDownloadCount", mock.Anything, "npm", "lodash", "4.17.21").Return(nil)
+
+	manager, err := New(mockStorage, mockMetadata, nil, nil, Config{})
+	require.NoError(t, err)
+
+	bc := &fakeBroadcaster{}
+	manager.SetBroadcaster(bc)
+
+	fetch := func(ctx context.Context) (io.ReadCloser, string, error) {
+		return io.NopCloser(strings.NewReader("upstream data")), "https://registry.npmjs.org/lodash", nil
+	}
+	entry, err := manager.Get(context.Background(), "npm", "lodash", "4.17.21", fetch)
+	require.NoError(t, err)
+	require.NotNil(t, entry)
+
+	types := bc.typesOnly()
+	require.Contains(t, types, string(websocket.EventPackageCached))
+	require.NotContains(t, types, string(websocket.EventPackageDownloaded),
+		"miss-then-fetch path should not emit EventPackageDownloaded")
+
+	// Inspect EventPackageCached payload.
+	var cachedEv *fakeBroadcastEvent
+	for i := range bc.events {
+		if bc.events[i].Type == string(websocket.EventPackageCached) {
+			cachedEv = &bc.events[i]
+			break
+		}
+	}
+	require.NotNil(t, cachedEv)
+	payload, ok := cachedEv.Payload.(map[string]interface{})
+	require.True(t, ok)
+	assert.Equal(t, "npm", payload["registry"])
+	assert.Equal(t, "lodash", payload["name"])
+	assert.Equal(t, "4.17.21", payload["version"])
+	assert.Equal(t, int64(len("upstream data")), payload["size"])
+	// Scanner is nil in this test → scan_status should be "disabled".
+	assert.Equal(t, "disabled", payload["scan_status"])
+}
+
+// TestBroadcaster_NoEmitOnError ensures error paths (storage Put fail,
+// metadata Save fail) do NOT emit EventPackageCached.
+func TestBroadcaster_NoEmitOnError(t *testing.T) {
+	t.Run("storage put fails", func(t *testing.T) {
+		mockStorage := &MockStorageBackend{}
+		mockMetadata := &MockMetadataStore{}
+
+		mockMetadata.On("GetPackage", mock.Anything, "npm", "fail", "1.0.0").Return(nil, errors.New("not found"))
+		mockStorage.On("GetQuota", mock.Anything).Return(&storage.QuotaInfo{Used: 100, Available: 900, Limit: 1000}, nil)
+		mockStorage.On("Put", mock.Anything, "npm/fail/1.0.0", mock.Anything, mock.Anything).Return(errors.New("storage error"))
+
+		manager, err := New(mockStorage, mockMetadata, nil, nil, Config{})
+		require.NoError(t, err)
+
+		bc := &fakeBroadcaster{}
+		manager.SetBroadcaster(bc)
+
+		fetch := func(ctx context.Context) (io.ReadCloser, string, error) {
+			return io.NopCloser(strings.NewReader("data")), "https://registry.npmjs.org/fail", nil
+		}
+		_, err = manager.Get(context.Background(), "npm", "fail", "1.0.0", fetch)
+		require.Error(t, err)
+
+		assert.Empty(t, bc.snapshot(), "no events should be emitted when storage Put fails")
+	})
+
+	t.Run("metadata save fails", func(t *testing.T) {
+		mockStorage := &MockStorageBackend{}
+		mockMetadata := &MockMetadataStore{}
+
+		mockMetadata.On("GetPackage", mock.Anything, "npm", "meta-fail", "1.0.0").Return(nil, errors.New("not found"))
+		mockStorage.On("GetQuota", mock.Anything).Return(&storage.QuotaInfo{Used: 100, Available: 900, Limit: 1000}, nil)
+		mockStorage.On("Put", mock.Anything, "npm/meta-fail/1.0.0", mock.Anything, mock.Anything).Return(nil)
+		mockMetadata.On("SavePackage", mock.Anything, mock.Anything).Return(errors.New("metadata error"))
+		mockStorage.On("Delete", mock.Anything, "npm/meta-fail/1.0.0").Return(nil)
+
+		manager, err := New(mockStorage, mockMetadata, nil, nil, Config{})
+		require.NoError(t, err)
+
+		bc := &fakeBroadcaster{}
+		manager.SetBroadcaster(bc)
+
+		fetch := func(ctx context.Context) (io.ReadCloser, string, error) {
+			return io.NopCloser(strings.NewReader("data")), "https://registry.npmjs.org/meta-fail", nil
+		}
+		_, err = manager.Get(context.Background(), "npm", "meta-fail", "1.0.0", fetch)
+		require.Error(t, err)
+
+		assert.Empty(t, bc.snapshot(), "no events should be emitted when metadata SavePackage fails")
+	})
+
+	t.Run("nil broadcaster is safe", func(t *testing.T) {
+		mockStorage := &MockStorageBackend{}
+		mockMetadata := &MockMetadataStore{}
+
+		now := time.Now()
+		expiresAt := now.Add(24 * time.Hour)
+		pkg := &metadata.Package{
+			ID:           "id",
+			Registry:     "npm",
+			Name:         "x",
+			Version:      "1",
+			StorageKey:   "npm/x/1",
+			CachedAt:     now,
+			LastAccessed: now,
+			ExpiresAt:    &expiresAt,
+		}
+		mockMetadata.On("GetPackage", mock.Anything, "npm", "x", "1").Return(pkg, nil)
+		mockStorage.On("Get", mock.Anything, "npm/x/1").Return(io.NopCloser(strings.NewReader("d")), nil)
+		mockMetadata.On("UpdateDownloadCount", mock.Anything, "npm", "x", "1").Return(nil)
+
+		manager, err := New(mockStorage, mockMetadata, nil, nil, Config{})
+		require.NoError(t, err)
+		// No SetBroadcaster — manager.broadcaster is nil.
+		_, err = manager.Get(context.Background(), "npm", "x", "1", nil)
+		require.NoError(t, err)
+	})
+}