fix(ui): native safe-area under Android 15+ edge-to-edge (WebView < 140)

targetSdk 36 forces edge-to-edge, so the WebView draws behind the system
bars. On Android WebView < 140, env(safe-area-inset-*) wrongly reports 0, so
the app chrome (which only read env()) drew under the status bar (top nav
untappable) and the gesture-nav home indicator (the game's centre Hint button
intercepted; side buttons fine). Capacitor 8's SystemBars core plugin (built
into @capacitor/core, insetsHandling:'css' by default) injects the correct
--safe-area-inset-* values on every WebView; consume them ahead of env():

  --tg-safe-*: var(--safe-area-inset-*, env(safe-area-inset-*, 0px))

Web / PWA / Telegram / VK are unchanged (--safe-area-inset-* is unset there,
so it falls back to env()). Verified on-device (Pixel_10 / API 37) via the
injected var — the emulator's auto-updated WebView 149 hides the env() bug,
so the visual alone won't reproduce it.

ui/src/components/DictWarmup.svelte

@@ -53,7 +53,8 @@
     place-items: center;
     /* Darker than the onboarding scrim — this blocks the board until the dictionary is ready. */
     background: rgba(0, 0, 0, 0.72);
-    padding: env(safe-area-inset-top) env(safe-area-inset-right) env(safe-area-inset-bottom) env(safe-area-inset-left);
+    /* Via the shared --tg-safe-* tokens so the Android WebView < 140 env() bug is covered (app.css). */
+    padding: var(--tg-safe-top) var(--tg-safe-right) var(--tg-safe-bottom) var(--tg-safe-left);
   }
   .box {
     display: grid;