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/tips.go

@@ -14,6 +14,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/steveyegge/beads/internal/beads"
 	"github.com/steveyegge/beads/internal/storage"
 )
 
@@ -353,6 +354,30 @@ func initDefaultTips() {
 			return isClaudeDetected() && !isClaudeSetupComplete()
 		},
 	)
+
+	// Sync conflict tip - ALWAYS show when sync has failed and needs manual intervention
+	// This is a proactive health check that trumps educational tips (ox-cli pattern)
+	InjectTip(
+		"sync_conflict",
+		"Run 'bd sync' to resolve sync conflict",
+		200,         // Higher than Claude setup - sync issues are urgent
+		0,           // No frequency limit - always show when applicable
+		1.0,         // 100% probability - always show when condition is true
+		syncConflictCondition,
+	)
+}
+
+// syncConflictCondition checks if there's a sync conflict that needs manual resolution.
+// This is the condition function for the sync_conflict tip.
+func syncConflictCondition() bool {
+	// Find beads directory to check sync state
+	beadsDir := beads.FindBeadsDir()
+	if beadsDir == "" {
+		return false
+	}
+
+	state := LoadSyncState(beadsDir)
+	return state.NeedsManualSync
 }
 
 // init initializes the tip system with default tips