Decouple dialog refocus from PanelsService via FocusService

Dialogs only needed refocus(); injecting PanelsService boots a whole
workspace, which secondary windows must not do.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

ui/src/app/dialogs/chmod-dialog.ts

@@ -1,6 +1,6 @@
 import { Component, computed, inject, input, signal } from '@angular/core';
 import { DialogsService, type ChmodRequest } from '../dialogs.service';
-import { PanelsService } from '../panels.service';
+import { FocusService } from '../focus.service';
 
 const ROLES = ['Owner', 'Group', 'Others'] as const;
 const PERMS = ['r', 'w', 'x'] as const;
@@ -81,7 +81,7 @@ export class ChmodDialog {
   readonly perms = PERMS;
 
   private readonly dialogs = inject(DialogsService);
-  private readonly panels = inject(PanelsService);
+  private readonly focus = inject(FocusService);
 
   // mode is initialized lazily from the request on first read
   private readonly modeOverride = signal<number | null>(null);
@@ -120,6 +120,6 @@ export class ChmodDialog {
 
   private close(): void {
     this.dialogs.chmod.set(null);
-    this.panels.refocus();
+    this.focus.bump();
   }
 }