controller v0.67.0: intermediary-mount — HDD_PATH repoint + drive-absent gate + H1 routes

Drives are visible in-guest only at the STABLE /mnt/felhom-drives/<name>; the
registered path + HDD_PATH + FileBrowser source repoint there while agent calls
map back to raw /mnt/<name> (agentWhere). Enroll binds-under-parent before
register. Drive-absent GATE (planDriveGates + 30s driveGateLoop) stops/blocks
apps when a drive vanishes and auto-restarts on return; start-gate refuses start
when the drive is absent. H1 endpoints (disconnect/reconnect/restart-apps) routed
onto host-side ops. Non-hollow tests + companions.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

controller/internal/settings/settings.go

@@ -535,6 +535,35 @@ func (s *Settings) RemoveStoragePath(path string) error {
 	return s.save()
 }
 
+// RepointStoragePath changes a registered path's Path string in place (intermediary-mount migration:
+// /mnt/<name> → /mnt/felhom-drives/<name>), preserving all other fields (label, default, schedulable,
+// disconnect/decommission state). No-op (nil) if oldPath isn't registered or already equals newPath.
+// Errors if newPath collides with a different existing entry.
+func (s *Settings) RepointStoragePath(oldPath, newPath string) error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if oldPath == newPath {
+		return nil
+	}
+	idx := -1
+	for i := range s.StoragePaths {
+		if s.StoragePaths[i].Path == newPath {
+			return fmt.Errorf("repoint target %q already registered", newPath)
+		}
+		if s.StoragePaths[i].Path == oldPath {
+			idx = i
+		}
+	}
+	if idx < 0 {
+		return nil // nothing to repoint
+	}
+	s.StoragePaths[idx].Path = newPath
+	if s.log != nil {
+		s.log.Printf("[INFO] [settings] Repointed storage path: %s → %s", oldPath, newPath)
+	}
+	return s.save()
+}
+
 // SetDefaultStoragePath changes which path is the default.
 func (s *Settings) SetDefaultStoragePath(path string) error {
 	s.mu.Lock()