fix(dashboard): UI polish — modals, layout, consistency, test fixes

Dashboard UX polish pass — consolidates create forms into modals
triggered from the page header, fixes layout inconsistencies, adds
scroll-to navigation for the Keys page, and aligns the TokenBar with
the design system.

Changes:
- App.tsx: add padding to sidebar header
- resolve-page-title.ts: add missing routes, better fallback title
- en.ts: fix nav labels (Profiles was 'profiles : multi agents')
- ModelsPage: two-col layout, auxiliary tasks modal, TokenBar redesign
- ProfilesPage: create button in header, form in modal, Checkbox component
- CronPage: create button in header, form in modal
- EnvPage: scroll-to sub-nav in header, fix text overflow

Modal and dialog standardization:
- Replace all native confirm()/window.confirm() with ConfirmDialog
  (OAuthProvidersCard, PluginsPage, ModelsPage, ConfigPage)
- Add useModalBehavior hook (Escape-to-close, scroll lock, focus restore)
- Apply hook to ProfilesPage, CronPage, AuxiliaryTasksModal

Component fixes (from PR review):
- Checkbox: fix controlled/uncontrolled mismatch, add focus-visible ring
- TokenBar: add rounded-full to legend dots, remove dead code

CI/test fixes:
- Fix TS unused imports (noUnusedLocals), type-narrow PickerTarget union
- Add windows-footgun suppression on platform-guarded os.killpg
- Fix 19 stale unit tests + 9 e2e tests broken by recent main changes
- Restore minimal example-dashboard plugin for plugin auth test

web/src/hooks/useModalBehavior.ts

@@ -0,0 +1,44 @@
+import { useEffect, useRef } from "react";
+
+/**
+ * Hook that adds standard modal behaviors when `open` is true:
+ * - Escape key calls `onClose`
+ * - Body scroll is locked
+ * - Focus is restored to the previously focused element on close
+ *
+ * Returns a ref to attach to the modal container (for optional future focus trapping).
+ */
+export function useModalBehavior({
+  open,
+  onClose,
+}: {
+  open: boolean;
+  onClose: () => void;
+}) {
+  const containerRef = useRef<HTMLDivElement>(null);
+
+  useEffect(() => {
+    if (!open) return;
+
+    const prevActive = document.activeElement as HTMLElement | null;
+
+    const onKey = (e: KeyboardEvent) => {
+      if (e.key === "Escape") {
+        e.preventDefault();
+        onClose();
+      }
+    };
+
+    document.addEventListener("keydown", onKey);
+    const prevOverflow = document.body.style.overflow;
+    document.body.style.overflow = "hidden";
+
+    return () => {
+      document.removeEventListener("keydown", onKey);
+      document.body.style.overflow = prevOverflow;
+      prevActive?.focus?.();
+    };
+  }, [open, onClose]);
+
+  return containerRef;
+}