Fix the dead win7 context menu, flatten the selection, add a tab menu

Right-click did nothing under the win7 skin, and then swallowed the next
click. 7.css declares `position: relative` on ul[role=menu] and the `skin`
layer outranks `utilities`, so Tailwind's `.fixed` lost: [style.left/top.px]
became flow offsets from the menu's static position — the last child of the
h-screen frame — and every menu rendered below the viewport, unreachable
behind overflow:hidden. Its backdrop is a plain <div>, unmatched by 7.css, so
that stayed genuinely fixed and ate the following click. Regressed in 0ae2a62,
when the menu adopted 7.css's real markup.

Restated `position: fixed` in skinfix, scoped to a new `w7-ctx` marker so
7.css's own menus keep theirs. scripts/menu-probe.ts is the regression test:
it renders the menu at declared coordinates, pixel-scans whether it landed
there, and carries a marker-less control menu (the bug verbatim) as its own
discriminator. A resting pixel diff cannot see this class of bug.

Selection band goes flat: --w7-sel-bg/-bd (#cbe8f6/#26a0da) is what Explorer
actually painted, where 7.css reused --w7-el-grad-h, its Aero element-hover
ramp. That var is left alone — buttons and tabs still want the gloss. The
unfocused pane gets the grey idle band; the band still never disappears with
focus, it only weakens. Harness diff confirms the change touches selection
rows and nothing else, in both themes.

New workspace-tab right-click menu in both skins: New Tab, Close Tab, Close
Other Tabs, Close Tabs to the Right, Disconnect. The target id travels inside
the action string because the right-clicked tab is not necessarily the active
one. Illegal entries are disabled rather than omitted, the way Win7 greyed
out — and since 7.css's [aria-disabled] handling is CSS-only, the keyboard
paths check the flag themselves.

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

ui/src/app/skins/7like/tab-bar/tab-bar.ts

@@ -3,8 +3,9 @@ import { NgIcon } from '@ng-icons/core';
 import { BRANDING } from '@shared/branding';
 import { LOCALE_LABELS, SUPPORTED } from '@shared/i18n';
 import type { AccentTone } from '@shared/types';
+import { ContextMenuService } from '@core/context-menu.service';
 import { I18nService } from '@core/i18n.service';
-import { PanelsService } from '@core/panels.service';
+import { PanelsService, type Workspace } from '@core/panels.service';
 import { APP_SKIN, MOD_LABEL } from '@core/platform';
 import { RpcService } from '@core/rpc.service';
 import { SettingsService } from '@core/settings.service';
@@ -71,6 +72,7 @@ const CONCURRENCY_CHOICES = [2, 3, 4, 6, 8] as const;
           [attr.data-tab-id]="ws.id"
           (click)="panels.setActiveWorkspace(ws.id)"
           (auxclick)="onAuxClick($event, ws.id)"
+          (contextmenu)="onTabContextMenu($event, ws, i)"
           class="flex max-w-52 min-w-0 shrink-0 items-center gap-1.5 electrobun-webkit-app-region-no-drag"
           [class.opacity-50]="draggedId() === ws.id"
           [style.box-shadow]="dropIndicatorShadow(i)"
@@ -467,6 +469,7 @@ export class TabBar {
   readonly settings = inject(SettingsService);
   readonly i18n = inject(I18nService);
   readonly updater = inject(UpdaterService);
+  private readonly contextMenu = inject(ContextMenuService);
   private readonly rpc = inject(RpcService);
   readonly settingsOpen = signal(false);
   readonly localeOptions = SUPPORTED;
@@ -526,6 +529,24 @@ export class TabBar {
     if (this.panels.workspaces().length > 1) this.close(event, id);
   }
 
+  /**
+   * Right-click a tab. The menu targets THIS tab, not the active one — its
+   * actions all carry the id — so right-clicking a background tab does not
+   * yank focus to it first, the way Explorer and every browser behave.
+   */
+  onTabContextMenu(event: MouseEvent, workspace: Workspace, index: number): void {
+    event.preventDefault();
+    this.contextMenu.open(
+      event,
+      this.contextMenu.tabItems({
+        id: workspace.id,
+        index,
+        tabCount: this.panels.workspaces().length,
+        isRemote: this.panels.workspaceIsRemote(workspace),
+      }),
+    );
+  }
+
   /** "Visual Studio Code.app" -> "Visual Studio Code"; empty -> system default. */
   editorAppName(): string {
     const path = this.settings.editorApp();