feat(i18n): presentation extraction — t() call sites, data-i18n templates, locale selector

Route every application-owned presentation string through the i18n
core: t() call sites across the app/layers/ui/data/voice surfaces,
data-i18n* attributes in the src/ui/templates/*.html markup (applied at
boot by applyDocumentTranslations from src/standalone/application.js),
and the dock locale selector (runtime-rendered from the offered pair —
a single EN button while only English ships).

Rebased onto current main, where the extraction follows the module
splits: the shell wiring now lands in the owner modules
(panelChrome, visualSettings, locationNavigation, shareRestoration,
shellFeedback, applicationShell) and the voice status corpus in the
realtime* modules; scene status lives in director.js +
playbackAdapter.js.

Modules shared with the node runtime (loadingFeedback,
installationFeedback, regionalModel, keySetupCore, vessels ingestion)
stay environment-neutral English and localize at their browser render
sites (chip maps in shellFeedback/installations controls, the weather
table in cockpitBriefing, keySetupRequirementEnvVars compositions), so
the package-boundary graph stays clean; the browser boundary groups
now own the i18n modules they reach (scripts/package-boundaries.json).

src/layers/bikeshare/controls.js

@@ -1,3 +1,4 @@
+import { t } from '../../i18n/index.js';
 import { STATUS_POLL_MS } from './policy.js';
 
 export function createControls({ state: layerState, services, parts, source }) {
@@ -34,8 +35,10 @@ export function createControls({ state: layerState, services, parts, source }) {
       if (layerState._loading) {
         stats.loadingLabel =
           layerState._activeCityIds.size > 0
-            ? `syncing ${layerState._activeCityIds.size} city feeds...`
-            : 'scanning nearby systems...';
+            ? t('layers.bike.loadingSyncing', {
+                count: layerState._activeCityIds.size,
+              })
+            : t('layers.bike.loadingScanning');
       }
       if (layerState._error) stats.error = layerState._error;
       return stats;