v1.1: fix transfer freeze, session tabs, per-panel toolbars, status bar

Freeze root cause: TransfersService consumed transferUpdate through an effect
that both read and wrote the jobMap signal — the first progress message spun
the effect into an infinite re-run loop, pegging the webview thread while the
copy completed fine bun-side. Push messages now flow through plain callback
registries on RpcService (also stops signal coalescing from dropping progress
snapshots). Verified live: a 60MB boot-time self-test copy streamed progress
into the running UI and the post-completion panel refreshes arrived.

- Tabs: workspaces (left+right PanelState pair each) in PanelsService; tab bar
  replaces the header; sessions persist in background tabs; Cmd+T/Cmd+W/Ctrl+Tab;
  closing a tab disconnects its sessions; last tab can't close
- Per-panel toolbar (top, icon-only): direction-explicit copy (-> / <-),
  rename, new folder/file, chmod, delete; panel footers removed
- VSCode-style status bar: transfer summary (spinner/percent/queued/failures,
  click to expand the job list) + active panel info; function bar removed
- transfer details list is collapsible, auto-expands on failure

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

ui/src/app/file-panel/file-panel.html

@@ -1,5 +1,5 @@
 <!-- session strip -->
-<div class="relative flex items-center gap-1.5 border-b border-border px-2 py-1.5">
+<div class="relative flex items-center gap-1.5 border-b border-border px-2 py-1">
   <button
     (click)="menuOpen.set(!menuOpen())"
     class="flex min-w-0 items-center gap-1.5 rounded-md px-2 py-1 text-xs font-medium hover:bg-accent"
@@ -27,6 +27,52 @@
     </button>
   }
 
+  <div class="flex-1"></div>
+
+  <!-- panel actions: act on THIS panel -->
+  <button
+    (click)="copyToOther()"
+    [title]="side() === 'left' ? 'Copy to right panel (F5)' : 'Copy to left panel (F5)'"
+    class="grid size-6 shrink-0 place-items-center rounded-md text-muted-foreground hover:bg-accent hover:text-primary"
+  >
+    <ng-icon [name]="copyIcon()" size="0.95rem" />
+  </button>
+  <button
+    (click)="run('rename')"
+    title="Rename (F2)"
+    class="grid size-6 shrink-0 place-items-center rounded-md text-muted-foreground hover:bg-accent hover:text-foreground"
+  >
+    <ng-icon name="mynaEdit" size="0.9rem" />
+  </button>
+  <button
+    (click)="run('mkdir')"
+    title="New folder (F7)"
+    class="grid size-6 shrink-0 place-items-center rounded-md text-muted-foreground hover:bg-accent hover:text-foreground"
+  >
+    <ng-icon name="mynaFolderPlus" size="0.9rem" />
+  </button>
+  <button
+    (click)="run('createFile')"
+    title="New file"
+    class="grid size-6 shrink-0 place-items-center rounded-md text-muted-foreground hover:bg-accent hover:text-foreground"
+  >
+    <ng-icon name="mynaFilePlus" size="0.9rem" />
+  </button>
+  <button
+    (click)="run('chmod')"
+    title="Permissions"
+    class="grid size-6 shrink-0 place-items-center rounded-md text-muted-foreground hover:bg-accent hover:text-foreground"
+  >
+    <ng-icon name="mynaLock" size="0.9rem" />
+  </button>
+  <button
+    (click)="run('delete')"
+    title="Delete (F8 / Del)"
+    class="grid size-6 shrink-0 place-items-center rounded-md text-muted-foreground hover:bg-accent hover:text-destructive"
+  >
+    <ng-icon name="mynaTrash" size="0.9rem" />
+  </button>
+
   @if (menuOpen()) {
     <div class="fixed inset-0 z-20" (click)="menuOpen.set(false)"></div>
     <div
@@ -135,7 +181,6 @@
   (keydown)="onKeydown($event)"
   (mousedown)="activate()"
   class="flex-1 overflow-y-auto outline-none"
-  [class.bg-accent]="false"
 >
   @for (entry of panel().sorted(); track entry.name; let i = $index) {
     <div
@@ -168,11 +213,3 @@
     <div class="p-6 text-center text-xs text-muted-foreground">Empty directory</div>
   }
 </div>
-
-<!-- footer -->
-<div class="flex items-center gap-2 border-t border-border px-2 py-1 text-[11px] text-muted-foreground">
-  <span>{{ panel().sorted().length }} items</span>
-  @if (panel().selected().size; as count) {
-    <span>· {{ count }} selected</span>
-  }
-</div>