fix: prevent internal prompts and duplicates in memory database

- Add server-side detection of SDK processor's internal system prompt
  in handleSessionInit, since CLAUDE_MNEMONIC_INTERNAL env var is not
  propagated by Claude Code to hook subprocesses
- Add cross-session duplicate detection (FindRecentPromptByTextGlobal)
  to catch same prompt text arriving from different session IDs
- Add hooks, mcpServers, and commands references to plugin.json per
  Claude Code plugin spec
- Remove MCP server injection from register-plugin.sh (now in plugin.json)
- Use ${CLAUDE_PLUGIN_ROOT} for statusline path instead of hardcoded path
- Add python3 fallback for plugin registration when jq is unavailable
- Replace hardcoded 1.0.0 version in findWorkerBinary with glob lookup
- Add cache copy verification in register-plugin.sh
- Add update-version Makefile target to keep metadata in sync

internal/db/interface.go

@@ -57,6 +57,7 @@ type PromptReader interface {
 	GetAllPrompts(ctx context.Context) ([]*models.UserPromptWithSession, error)
 	GetRecentUserPromptsByProject(ctx context.Context, project string, limit int) ([]*models.UserPromptWithSession, error)
 	FindRecentPromptByText(ctx context.Context, claudeSessionID, promptText string, withinSeconds int) (int64, int, bool)
+	FindRecentPromptByTextGlobal(ctx context.Context, promptText string, withinSeconds int) (int64, int, bool)
 }
 
 // PromptWriter defines write operations for prompts.