feat(i18n): translate five more systems, and check for updates more often

Update cadence: the desktop app checked once ten seconds after launch and
then every four hours. A release published while the app sits open went
unnoticed until the next poll — which is exactly what happened with 1.4.0.
It now polls every 30 minutes and also checks when the window regains focus,
throttled to one check per five minutes so alt-tabbing does not hammer the
feed. `lastCheckAt` is stamped from the `checking-for-update` event rather
than by the callers, so a manual check from the settings panel counts too.
The focus listener is on `app`, not on mainWindow, because the window is
destroyed and recreated when closed to tray.

Translations, five whole systems:
  - Settings > Desktop (autostart, updates, instance)
  - Settings > Voice: output device, which completes that tab
  - Settings > Keybinds, including the action names and conflict prompt
  - Settings > Account, the largest — profile, password, detached-instance
    notice, danger zone
  - Explore spaces

Two sentences wrap a literal that must not be translated (the `input` group
name, the `user@instance` example). Those are split around a placeholder
rather than interpolated as text, so a translation keeps control of the word
order on both sides of it. Keybind action labels gained a `labelKey`
alongside the English `label`, which stays for non-React callers.

Verified: web build (tsc + vite), desktop typecheck, 490 web tests.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

packages/desktop/src/main.ts

@@ -814,7 +814,14 @@ function initAutoUpdater(): void {
 
     let updateConfirmed = false;
 
+    // Cadence state. `lastCheckAt` is stamped from the event rather than from
+    // the callers, so a manual "check for updates" from the settings panel
+    // counts too and a focus arriving right after it doesn't check twice.
+    let lastCheckAt = 0;
+    let downloaded = false;
+
     autoUpdater.on('checking-for-update', () => {
+      lastCheckAt = Date.now();
       recoveryStore.update({ updateState: 'checking', lastCheckResult: null });
       updateConfirmed = false;
     });
@@ -836,6 +843,7 @@ function initAutoUpdater(): void {
     });
 
     autoUpdater.on('update-downloaded', (info: { version: string }) => {
+      downloaded = true;
       const version = info.version.slice(0, 32);
       recoveryStore.update({ updateState: 'downloaded', updateVersion: version });
       mainWindow?.webContents.send('update-downloaded', { version });
@@ -875,17 +883,28 @@ function initAutoUpdater(): void {
       }
     });
 
-    // Initial check with 10s delay (existing behavior)
-    setTimeout(() => {
-      updateConfirmed = false;
-      autoUpdater.checkForUpdates().catch(() => {});
-    }, 10_000);
+    // A release published while the app sits open used to go unnoticed until
+    // the next poll — the startup check had long since run, and four hours is
+    // a long time to look at a stale version. Poll more often, and also check
+    // when the user comes back to the window, which is exactly when they would
+    // notice an update anyway.
+    const POLL_INTERVAL_MS = 30 * 60 * 1000;
+    const MIN_GAP_MS = 5 * 60 * 1000;  // keeps alt-tabbing off the feed
 
-    // Periodic check every 4 hours (existing behavior)
-    setInterval(() => {
+    const maybeCheck = (): void => {
+      if (downloaded) return;  // already staged; nothing left to look for
+      if (Date.now() - lastCheckAt < MIN_GAP_MS) return;
       updateConfirmed = false;
       autoUpdater.checkForUpdates().catch(() => {});
-    }, 4 * 60 * 60 * 1000);
+    };
+
+    setTimeout(maybeCheck, 10_000);
+    setInterval(maybeCheck, POLL_INTERVAL_MS);
+
+    // App-level rather than mainWindow-level: the window is destroyed and
+    // recreated when closed to tray and reopened, and a listener bound to the
+    // old instance would go quiet after the first close.
+    app.on('browser-window-focus', maybeCheck);
   } catch {
     // Auto-updater unavailable — recovery surface still functions, just
     // without update affordances. autoUpdaterRef stays null; recovery action