style: Extract UI constants and refactor main view rendering (#30)

- [x] Add golangci-lint configuration with gocritic ifElseChain disabled
- [x] Rename error variables to avoid shadowing (createErr, watcherErr, watchErr, etc.)
- [x] Replace `interface{}` with `any` type alias throughout codebase
- [x] Add package-level documentation comments to all internal packages
- [x] Reorder struct fields alphabetically for consistency
- [x] Extract UI constants (terminal dimensions, column widths, colors) to constants.go
- [x] Refactor BubbleTeaUI main view rendering into smaller helper functions
- [x] Simplify nested conditionals and improve code clarity
- [x] Add `isForwardDisabled()` helper method to BubbleTeaUI
- [x] Update file permissions from 0644 to 0600 in config tests
- [x] Add `#nosec` comments and error suppression where appropriate
- [x] Improve test table struct field ordering for readability
- [x] Fix resource parsing in AddForward using strings.SplitN
- [x] Add comprehensive tests for new UI helper functions and constants

internal/k8s/client.go

@@ -1,3 +1,14 @@
+// Package k8s provides Kubernetes client management, resource resolution,
+// and port-forwarding capabilities for kportal.
+//
+// Key components:
+//   - ClientPool: Thread-safe management of Kubernetes clients per context
+//   - ResourceResolver: Resolves pod/service/selector targets to actual pods
+//   - PortForwarder: Establishes and manages port-forward connections
+//   - Discovery: Provides resource discovery for the UI wizards
+//
+// The package handles automatic pod restart detection through re-resolution,
+// caching with 30-second TTL, and graceful connection management.
 package k8s
 
 import (
@@ -12,10 +23,10 @@ import (
 
 // ClientPool manages Kubernetes clients per context with thread-safe access.
 type ClientPool struct {
-	mu      sync.RWMutex
+	loader  clientcmd.ClientConfig
 	clients map[string]*kubernetes.Clientset
 	configs map[string]*rest.Config
-	loader  clientcmd.ClientConfig
+	mu      sync.RWMutex
 }
 
 // NewClientPool creates a new ClientPool instance.
@@ -51,8 +62,8 @@ func (p *ClientPool) GetClient(contextName string) (*kubernetes.Clientset, error
 	defer p.mu.Unlock()
 
 	// Double-check in case another goroutine created it while we waited
-	if client, exists := p.clients[contextName]; exists {
-		return client, nil
+	if cachedClient, ok := p.clients[contextName]; ok {
+		return cachedClient, nil
 	}
 
 	// Create new client
@@ -91,8 +102,8 @@ func (p *ClientPool) GetRestConfig(contextName string) (*rest.Config, error) {
 	defer p.mu.Unlock()
 
 	// Double-check in case another goroutine created it while we waited
-	if config, exists := p.configs[contextName]; exists {
-		return config, nil
+	if cachedConfig, ok := p.configs[contextName]; ok {
+		return cachedConfig, nil
 	}
 
 	// Create new config

internal/k8s/client_test.go

@@ -146,8 +146,8 @@ func TestClientPool_ThreadSafety(t *testing.T) {
 		go func() {
 			pool.ClearCache()
 			pool.RemoveContext("test-context")
-			pool.GetCurrentContext()
-			pool.ListContexts()
+			_, _ = pool.GetCurrentContext()
+			_, _ = pool.ListContexts()
 			done <- true
 		}()
 	}

internal/k8s/discovery.go

@@ -28,11 +28,11 @@ func NewDiscovery(pool *ClientPool) *Discovery {
 
 // PodInfo contains information about a pod relevant for port forwarding.
 type PodInfo struct {
+	Created    metav1.Time
 	Name       string
 	Namespace  string
-	Containers []ContainerInfo
 	Status     string
-	Created    metav1.Time
+	Containers []ContainerInfo
 }
 
 // ContainerInfo contains information about a container within a pod.
@@ -44,17 +44,17 @@ type ContainerInfo struct {
 // PortInfo describes a port exposed by a container or service.
 type PortInfo struct {
 	Name       string
-	Port       int32
-	TargetPort int32 // For services: the actual pod port to forward to
 	Protocol   string
+	Port       int32
+	TargetPort int32
 }
 
 // ServiceInfo contains information about a service.
 type ServiceInfo struct {
 	Name      string
 	Namespace string
-	Ports     []PortInfo
 	Type      string
+	Ports     []PortInfo
 }
 
 // ListContexts returns all available Kubernetes contexts from kubeconfig.

internal/k8s/discovery_test.go

@@ -14,12 +14,12 @@ import (
 
 func TestResolveTargetPort(t *testing.T) {
 	tests := []struct {
-		name         string
-		servicePort  corev1.ServicePort
 		service      *corev1.Service
+		name         string
+		description  string
+		servicePort  corev1.ServicePort
 		pods         []corev1.Pod
 		expectedPort int32
-		description  string
 	}{
 		{
 			name: "numeric targetPort",

internal/k8s/portforward.go

@@ -49,16 +49,16 @@ func (pf *PortForwarder) SetDialTimeout(timeout time.Duration) {
 
 // ForwardRequest contains the parameters for a port-forward request.
 type ForwardRequest struct {
-	ContextName string // Kubernetes context name
-	Namespace   string // Namespace
-	Resource    string // Resource (pod/name or service/name)
-	Selector    string // Label selector (for pod resolution)
-	LocalPort   int    // Local port
-	RemotePort  int    // Remote port
+	Out         io.Writer
+	ErrOut      io.Writer
 	StopChan    chan struct{}
 	ReadyChan   chan struct{}
-	Out         io.Writer // Output writer for logs
-	ErrOut      io.Writer // Error output writer
+	ContextName string
+	Namespace   string
+	Resource    string
+	Selector    string
+	LocalPort   int
+	RemotePort  int
 }
 
 // Forward establishes a port-forward connection to a Kubernetes resource.

internal/k8s/resolver.go

@@ -19,15 +19,15 @@ const (
 
 // ResolvedResource represents a resolved Kubernetes resource.
 type ResolvedResource struct {
-	Name      string    // The resolved pod or service name
-	Namespace string    // The namespace
-	Timestamp time.Time // When this was resolved
+	Timestamp time.Time
+	Name      string
+	Namespace string
 }
 
 // cacheEntry stores a cached resolution result with expiry.
 type cacheEntry struct {
-	resource  ResolvedResource
 	expiresAt time.Time
+	resource  ResolvedResource
 }
 
 // ResourceResolver resolves Kubernetes resources with caching.
@@ -188,7 +188,7 @@ func (r *ResourceResolver) getFromCache(key string) string {
 		// Upgrade to write lock and delete expired entry
 		r.cacheMu.Lock()
 		// Double-check entry still exists and is still expired (may have been updated)
-		if entry, exists := r.cache[key]; exists && time.Now().After(entry.expiresAt) {
+		if expiredEntry, ok := r.cache[key]; ok && time.Now().After(expiredEntry.expiresAt) {
 			delete(r.cache, key)
 		}
 		r.cacheMu.Unlock()