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/app.html

@@ -1,19 +1,4 @@
 <div class="flex h-screen flex-col bg-background text-foreground">
-  <header class="flex items-center gap-2 border-b border-border px-3 py-1.5">
-    <ng-icon name="mynaArrowLeftRight" class="text-muted-foreground" size="0.9rem" />
-    <h1 class="text-[13px] font-semibold tracking-tight">{{ appName }}</h1>
-    <div class="flex-1"></div>
-    @if (rpc.available) {
-      <button
-        (click)="dialogs.manager.set(true)"
-        title="Manage connections"
-        class="grid size-6 place-items-center rounded-md text-muted-foreground hover:bg-accent hover:text-foreground"
-      >
-        <ng-icon name="mynaCog" size="0.95rem" />
-      </button>
-    }
-  </header>
-
   @if (!rpc.available) {
     <div class="flex flex-1 items-center justify-center">
       <div class="max-w-sm rounded-lg border border-border bg-card p-6 text-center shadow-sm">
@@ -25,58 +10,15 @@
       </div>
     </div>
   } @else {
+    <app-tab-bar />
+
     <main class="flex min-h-0 flex-1 divide-x divide-border">
       <app-file-panel side="left" />
       <app-file-panel side="right" />
     </main>
 
     <app-transfer-bar />
-
-    <!-- function bar: acts on the active panel -->
-    <footer class="flex items-center gap-1 border-t border-border px-2 py-1">
-      <button
-        (click)="transfers.copyToOtherPanel()"
-        title="Copy to other panel (F5)"
-        class="flex items-center gap-1.5 rounded-md px-2 py-1 text-xs text-muted-foreground hover:bg-accent hover:text-foreground"
-      >
-        <ng-icon name="mynaArrowLeftRight" size="0.9rem" /> Copy
-      </button>
-      <button
-        (click)="actions.rename()"
-        title="Rename (F2)"
-        class="flex items-center gap-1.5 rounded-md px-2 py-1 text-xs text-muted-foreground hover:bg-accent hover:text-foreground"
-      >
-        <ng-icon name="mynaEdit" size="0.9rem" /> Rename
-      </button>
-      <button
-        (click)="actions.mkdir()"
-        title="New folder (F7)"
-        class="flex items-center gap-1.5 rounded-md px-2 py-1 text-xs text-muted-foreground hover:bg-accent hover:text-foreground"
-      >
-        <ng-icon name="mynaFolderPlus" size="0.9rem" /> Folder
-      </button>
-      <button
-        (click)="actions.createFile()"
-        title="New file"
-        class="flex items-center gap-1.5 rounded-md px-2 py-1 text-xs text-muted-foreground hover:bg-accent hover:text-foreground"
-      >
-        <ng-icon name="mynaFilePlus" size="0.9rem" /> File
-      </button>
-      <button
-        (click)="actions.chmod()"
-        title="Permissions"
-        class="flex items-center gap-1.5 rounded-md px-2 py-1 text-xs text-muted-foreground hover:bg-accent hover:text-foreground"
-      >
-        <ng-icon name="mynaLock" size="0.9rem" /> Permissions
-      </button>
-      <button
-        (click)="actions.delete()"
-        title="Delete (F8 / Del)"
-        class="flex items-center gap-1.5 rounded-md px-2 py-1 text-xs text-muted-foreground hover:bg-accent hover:text-destructive"
-      >
-        <ng-icon name="mynaTrash" size="0.9rem" /> Delete
-      </button>
-    </footer>
+    <app-status-bar />
   }
 
   <!-- dialogs -->
@@ -94,7 +36,7 @@
   }
 
   <!-- toasts -->
-  <div class="pointer-events-none fixed right-3 bottom-3 z-50 flex w-80 flex-col gap-2">
+  <div class="pointer-events-none fixed right-3 bottom-8 z-50 flex w-80 flex-col gap-2">
     @for (t of toast.toasts(); track t.id) {
       <div
         class="pointer-events-auto flex items-start gap-2 rounded-lg border border-border bg-card p-3 text-xs text-card-foreground shadow-lg"