refactor(db): thread context.Context through all Store methods

Enables request-scoped cancellation, timeouts, and graceful shutdown
for all database operations across API handlers, CLI commands, and TUI.

cmd/demote.go

@@ -19,19 +19,19 @@ func init() {
 	rootCmd.AddCommand(demoteCmd)
 }
 
-func runDemote(_ *cobra.Command, args []string) error {
+func runDemote(cmd *cobra.Command, args []string) error {
 	store, err := openStore()
 	if err != nil {
 		return err
 	}
 	defer store.Close()
 
-	id, err := store.Resolve(args[0])
+	id, err := store.Resolve(cmd.Context(), args[0])
 	if err != nil {
 		return fmt.Errorf("not_found — no entity with id %s", args[0])
 	}
 
-	if err := store.Demote(id); err != nil {
+	if err := store.Demote(cmd.Context(), id); err != nil {
 		if err == db.ErrAlreadyFluid {
 			return fmt.Errorf("invalid_demote — entity %s is already fluid", display.FormatID(id))
 		}