fix(vk): friend-code link as ?hash, Android safe-area via bridge insets, landscape home-bar colour

Contour review of the VK Bridge group:

- #6 invite link: VK's documented '#' direct-link payload is eaten by the vk.com SPA before it
  reaches the app, so the friend-code link now carries the payload as a query param
  (vk.com/app<id>?hash=f<code>); the recipient already reads the `hash` query param (vkStartParam).
  (Whether VK forwards the '?' through to the iframe is being confirmed on the contour.)
- #8 Android: the VK mobile webview does not surface the home-bar inset via CSS env() (config
  insets are iOS-only), so subscribe to the bridge insets (VKWebAppUpdateConfig + VKWebAppUpdateInsets)
  and set --tg-safe-* to max(env(), the VK value).
- #8 landscape colour: the home-indicator strip was the (grey) page background because the two-pane
  landscape game has no bottom bar. The left-panel controls bar now paints its own chrome into the
  inset (Screen gains a selfInset flag that drops the shell's detached padding strip), and the
  game-land runs flush to the edge.

Verified: svelte-check, 347 unit, build, bundle-gate; the landscape safe-area painting reproduced in
the mock (controls bar + board reach the edge, strip takes the bar colour). The VK-Bridge / VK launch
behaviours (Android insets, the ?hash forward) need the live contour.

ui/src/lib/deeplink.test.ts

@@ -45,9 +45,9 @@ describe('vkShareLink', () => {
     expect(vkShareLink('f123456')).toBeNull();
   });
 
-  it('wraps the payload in a vk.com/app direct link after the hash', () => {
+  it('wraps the payload in a vk.com/app link as the hash query param', () => {
     vi.stubGlobal('location', { search: '?vk_app_id=6736218&vk_user_id=1&sign=x' });
-    expect(vkShareLink('f123456')).toBe('https://vk.com/app6736218#f123456');
+    expect(vkShareLink('f123456')).toBe('https://vk.com/app6736218?hash=f123456');
   });
 });