feat(app): improve workspace service controls

Keep service route choices independent of daemon transport and persist the selected route per host. Use the shared web overlay stack so menus, tooltips, and toasts layer predictably.

Track proxy route changes from the Git branch rather than the workspace title to avoid transient service health changes.

packages/app/src/lib/overlay-root.ts

@@ -5,6 +5,7 @@
  * Z-index scale within overlay root:
  * - Modal backdrop/content: 10
  * - Toast: 20
+ * - Tooltip: 30
  */
 export function getOverlayRoot(): HTMLElement {
   let el = document.getElementById("overlay-root");
@@ -22,4 +23,5 @@ export function getOverlayRoot(): HTMLElement {
 export const OVERLAY_Z = {
   modal: 10,
   toast: 20,
+  tooltip: 30,
 } as const;