feat(e24): reach the Home surface — the landing toggle, a palette command, Shift+W

S4's reachability half. Home already led the nav order; what was missing was every
way IN other than the rail.

- Settings → Appearance → Startup: "Start on Home", the documented escape hatch for
  the landing override. Deliberately still localStorage and not a server pref —
  `loadInitialPage` answers before /api/me lands, and a landing module decided after
  the first paint is a visible jump. Its two stored values are now ONE exported
  constant, so the writer and the boot-time reader cannot drift on a magic string.
- The command palette gets "Meglepetés" / "Surprise me": it navigates to Home and
  rerolls the hero on arrival. No second "Mit nézzek?" row beside it — the Home
  module row already matches that phrase through its descriptive title.
- A global Shift+W jumps to Home. A chord, not a bare `w`: the Plex player binds bare
  letters and `w` sits on `s`, so a blind reach for the subtitle key would have thrown
  a viewer out of the film.

The palette's request crosses a lazy module boundary, so it is a token that waits
(lib/homeIntent) rather than an event fired into an empty room. Browser-measured:
taken with a compare-and-clear, because StrictMode's double-invoked mount effect
otherwise rerolled twice and landed on the page two picks deep.

HU/EN parity kept; UAT on localdev in both languages, including the empty shelf.

frontend/src/components/navigationInit.ts

@@ -6,10 +6,16 @@ import { hasFilterParams, isPage, readPage, type Page } from "../lib/urlState";
 import { getAccountRaw, LS } from "../lib/storage";
 
 export const PAGE_KEY = LS.page;
-// Module-local: the Settings opt-out (S4) writes `LS.startOnHome` directly, so exporting this
-// alias would only be a second name for the same key.
+// Module-local: the Settings toggle writes `LS.startOnHome` directly, so exporting this alias would
+// only be a second name for the same key.
 const START_HOME_KEY = LS.startOnHome;
 
+/** The two stored values of the landing preference (raw strings, via useAccountPersistedState).
+ *  Settings → Appearance → Startup writes them and `loadInitialPage` reads them, so they are defined
+ *  ONCE: the same magic string spelled out in a writer and a reader is precisely the drift that has
+ *  bitten this codebase before (`cancelled` vs `canceled`). */
+export const START_ON_HOME = { on: "1", off: "0" } as const;
+
 export interface ChannelView {
   id: string;
   name?: string;
@@ -26,8 +32,9 @@ export function loadInitialPage(): Page {
   // A bare URL → Home (E24), the surface whose whole job is to answer "what should I watch" before
   // the user has to decide anything. It deliberately OVERRIDES the remembered last module: landing
   // on whatever you happened to close the app on is the behaviour the anti-paralysis epic exists to
-  // replace. The account can opt out (Settings) and get the remembered module back.
-  if (getAccountRaw(START_HOME_KEY) !== "0") return "home";
+  // replace. The account can opt out (Settings → Appearance → Startup) and get the remembered
+  // module back.
+  if (getAccountRaw(START_HOME_KEY) !== START_ON_HOME.off) return "home";
   const stored = getAccountRaw(PAGE_KEY);
   return isPage(stored) ? stored : "feed";
 }