fix(keys): epic-end review round 1 — Back, menus and dialogs keep the focus where it belongs

Deep-review of E11 (19 raised, 14 confirmed; 2 refuted, 3 latent test-hardening notes dropped).

- Back from a sub-view (a Plex show page, a Messages thread) restores the item it was opened from
  even when focus was still inside the view: the first attempt now waits one task, past the
  sub-view's own popstate listener (measured in Chrome: it left focus on <body>).
- The restore listener is installed at load, so the first Back after a reload finds it; a push
  cancels a restore still waiting for the last landing's lists.
- Navigating over an overlay asks it again, a render apart, while its entry stays: the Plex
  player peels one panel per Back step, so Shift+W over info + stats closed one panel and dropped
  the navigation.
- j/k: a native <button> item keeps its own Tab stop; landing twice on the same item no longer
  leaks its tabindex; after the focused item is removed (a hidden card) the next j goes on from
  its slot when that slot is on screen.
- An abandoned `g` no longer swallows a modifier chord (g, then Mod+K opened the browser search).
- A hover card above a dialog no longer switches its Tab trap off (player, Modal, wizard,
  Lightbox): new layerStack `anyBlockingLayerAbove`.
- "Manage views…" closes its menu before opening the dialog, through a shared `closeThenAct`
  that ActionMenu now uses too.
- Copy: the EN welcome says "Feed"; the EN unreachable reason no longer claims a change;
  stale comments about PlayerModal's scroll lock and dialog contract.

frontend/src/components/ui/Modal.tsx

@@ -3,7 +3,7 @@ import { createPortal } from "react-dom";
 import { useTranslation } from "react-i18next";
 import { X } from "lucide-react";
 import { useBackToClose } from "../../lib/history";
-import { pushLayer, removeLayer, isTopmost } from "../../lib/layerStack";
+import { anyBlockingLayerAbove, pushLayer, removeLayer, isTopmost } from "../../lib/layerStack";
 import { useFullscreenPortalHost } from "../../lib/fullscreen";
 import { trapTab, useDialogChrome } from "./dialogFocus";
 import { Button } from "./Button";
@@ -61,15 +61,15 @@ export default function Modal({
   useEffect(() => {
     const id = pushLayer();
     const onKey = (e: KeyboardEvent) => {
-      if (!isTopmost(id)) return;
-      if (e.key === "Escape") {
+      if (e.key === "Escape" && isTopmost(id)) {
         e.stopPropagation();
         onCloseRef.current();
         return;
       }
       // Focus trap: keep Tab / Shift+Tab cycling inside the dialog instead of reaching the inert
-      // page behind the backdrop. Only the topmost modal traps (a nested one defers to its child).
-      if (e.key === "Tab") {
+      // page behind the backdrop. A nested modal or a click-opened menu above traps for itself; a hover
+      // card open under the pointer (a passive layer) does not, so it must not switch the trap off.
+      if (e.key === "Tab" && !anyBlockingLayerAbove(id)) {
         const panel = panelRef.current;
         if (!panel) return;
         // The whole dialog, not just the panel: its toast host sits beside the panel (see ui/Toaster),