P2: file operations with dialogs (mkdir, new file, rename, delete, chmod)

- prompt/confirm/chmod dialogs (signals-driven via DialogsService)
- FileActionsService: acts on selection or cursor row of the active panel
- function bar + F2/F7/F8/Delete keys; delete confirms and recurses
- verified provider ops + walkTree + removeRecursive on a scratch tree

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

ui/src/app/app.ts

@@ -1,19 +1,26 @@
 import { Component, inject } from '@angular/core';
 import { NgIcon } from '@ng-icons/core';
 import { BRANDING } from '@shared/branding';
+import { ChmodDialog } from './dialogs/chmod-dialog';
+import { ConfirmDialog } from './dialogs/confirm-dialog';
+import { PromptDialog } from './dialogs/prompt-dialog';
+import { DialogsService } from './dialogs.service';
+import { FileActionsService } from './file-actions.service';
 import { FilePanel } from './file-panel/file-panel';
 import { RpcService } from './rpc.service';
 import { ToastService } from './toast.service';
 
 @Component({
   selector: 'app-root',
-  imports: [NgIcon, FilePanel],
+  imports: [NgIcon, FilePanel, PromptDialog, ConfirmDialog, ChmodDialog],
   templateUrl: './app.html',
 })
 export class App {
   readonly appName = BRANDING.appName;
   readonly rpc = inject(RpcService);
   readonly toast = inject(ToastService);
+  readonly dialogs = inject(DialogsService);
+  readonly actions = inject(FileActionsService);
 
   constructor() {
     document.title = BRANDING.appName;