refactor: remove unused bd pin/unpin/hook commands (bd-x0zl)

Analysis found these commands are dead code:
- gt never calls `bd pin` - uses `bd update --status=pinned` instead
- Beads.Pin() wrapper exists but is never called
- bd hook functionality duplicated by gt mol status
- Code comment says "pinned field is cosmetic for bd hook visibility"

Removed:
- cmd/bd/pin.go
- cmd/bd/unpin.go
- cmd/bd/hook.go

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

cmd/bd/ready.go

@@ -39,6 +39,7 @@ This is useful for agents executing molecules to see which steps can run next.`,
 		labels, _ := cmd.Flags().GetStringSlice("label")
 		labelsAny, _ := cmd.Flags().GetStringSlice("label-any")
 		issueType, _ := cmd.Flags().GetString("type")
+		parentID, _ := cmd.Flags().GetString("parent")
 		// Use global jsonOutput set by PersistentPreRun (respects config.yaml + env vars)
 
 		// Normalize labels: trim, dedupe, remove empty
@@ -69,6 +70,9 @@ This is useful for agents executing molecules to see which steps can run next.`,
 		if assignee != "" && !unassigned {
 			filter.Assignee = &assignee
 		}
+		if parentID != "" {
+			filter.ParentID = &parentID
+		}
 		// Validate sort policy
 		if !filter.SortPolicy.IsValid() {
 			fmt.Fprintf(os.Stderr, "Error: invalid sort policy '%s'. Valid values: hybrid, priority, oldest\n", sortPolicy)
@@ -84,6 +88,7 @@ This is useful for agents executing molecules to see which steps can run next.`,
 				SortPolicy: sortPolicy,
 				Labels:     labels,
 				LabelsAny:  labelsAny,
+				ParentID:   parentID,
 			}
 			if cmd.Flags().Changed("priority") {
 				priority, _ := cmd.Flags().GetInt("priority")
@@ -229,12 +234,17 @@ var blockedCmd = &cobra.Command{
 			var err error
 			store, err = sqlite.New(ctx, dbPath)
 			if err != nil {
-			fmt.Fprintf(os.Stderr, "Error: failed to open database: %v\n", err)
-			os.Exit(1)
+				fmt.Fprintf(os.Stderr, "Error: failed to open database: %v\n", err)
+				os.Exit(1)
 			}
 			defer func() { _ = store.Close() }()
-			}
-		blocked, err := store.GetBlockedIssues(ctx)
+		}
+		parentID, _ := cmd.Flags().GetString("parent")
+		var blockedFilter types.WorkFilter
+		if parentID != "" {
+			blockedFilter.ParentID = &parentID
+		}
+		blocked, err := store.GetBlockedIssues(ctx, blockedFilter)
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "Error: %v\n", err)
 			os.Exit(1)
@@ -410,6 +420,8 @@ func init() {
 	readyCmd.Flags().StringSlice("label-any", []string{}, "Filter by labels (OR: must have AT LEAST ONE). Can combine with --label")
 	readyCmd.Flags().StringP("type", "t", "", "Filter by issue type (task, bug, feature, epic, merge-request)")
 	readyCmd.Flags().String("mol", "", "Filter to steps within a specific molecule")
+	readyCmd.Flags().String("parent", "", "Filter to descendants of this bead/epic")
 	rootCmd.AddCommand(readyCmd)
+	blockedCmd.Flags().String("parent", "", "Filter to descendants of this bead/epic")
 	rootCmd.AddCommand(blockedCmd)
 }