Add hover-reveal edit button to widget cards + auto-open edit mode

Each widget card now shows a settings icon in the top-right corner on
hover (desktop) or always-visible (mobile via mobile-touch-target).
Clicking it opens the WidgetConfigDialog directly in edit mode for that
widget (via a new editWidgetId prop on WidgetConfigDialog that
auto-enters the draft-edit path via useEffect).

Wired across all three widget surfaces:
- Dashboard (both mobile section + desktop grid)
- Service OverviewTab
- NamedDashboardPage

128 tests pass; build/lint green.

frontend/src/components/WidgetConfigDialog.tsx

@@ -1,4 +1,4 @@
-import { useMemo, useState } from "react";
+import { useEffect, useMemo, useState } from "react";
 import {
 	Dialog,
 	DialogContent,
@@ -56,6 +56,8 @@ interface Props {
 	serviceId?: string;
 	/** When set, enable widget references ("Add existing") for this dashboard scope. */
 	dashboardScope?: string;
+	/** When set, auto-open in edit mode for this widget id (instead of the list view). */
+	editWidgetId?: string;
 }
 
 interface Draft {
@@ -203,6 +205,7 @@ export function WidgetConfigDialog({
 	onClose,
 	serviceId,
 	dashboardScope,
+	editWidgetId,
 }: Props) {
 	const { data: instances = [] } = useWidgetInstances(serviceId);
 	const { data: services = [] } = useServiceInstances();
@@ -220,6 +223,18 @@ export function WidgetConfigDialog({
 
 	const [draft, setDraft] = useState<Draft | null>(null);
 
+	// When editWidgetId is set and the dialog opens, auto-enter edit mode for
+	// that widget (instead of showing the list view).
+	useEffect(() => {
+		if (open && editWidgetId && instances.length > 0) {
+			const target = instances.find((w) => w.id === editWidgetId);
+			if (target) {
+				startEdit(target);
+			}
+		}
+		 
+	}, [open, editWidgetId, instances]);
+
 	function startAddBuiltIn(kind: string) {
 		const binding = BUILTIN_WIDGETS[kind];
 		setDraft({