feat(android): resolve gateway origin on native, skip SW, hide MVP purchases

Make the web SPA behave correctly inside the Capacitor native shell, where the
bundle loads from a local origin:

- New lib/origin.ts gatewayOrigin(): absolute URLs resolve to VITE_GATEWAY_URL on
  native (the finished-game export/share URL in Game.svelte and the Wallet
  site-root link), falling back to the page origin on web. transport.ts already
  resolved via VITE_GATEWAY_URL and is left as-is.
- Skip the PWA service worker on the native channel (the assets are already local;
  a worker would risk serving stale content across store updates).
- Hide the money-purchase UI in the MVP: new distribution.purchasesHidden() folds
  VITE_PAYMENTS_DISABLED and the Google Play flag. The Wallet "buy" tab shows a
  neutral, pointer-free note (wallet.purchasesSoon) for the RuStore MVP and keeps
  the RuStore stub Google-Play-only. A ?nopay mock force mirrors ?gp for the e2e.
- Native env types in vite-env.d.ts.

Client-only, contour-safe: no wire/proto/schema change; web/VK/Telegram unchanged.
Tests: origin + purchasesHidden unit tests, a ?nopay wallet e2e. svelte-check
clean, vitest green, web + native vite build clean.

ANDROID_PLAN.md

@@ -71,7 +71,17 @@ Kept current as parts land so a fresh session resumes without re-deriving. Verif
   **Launcher icon:** a **temporary** placeholder is in place — `ui/assets/icon.png` (the maskable «Э»
   brand mark upscaled 512→1024) → `pnpm android:assets` regenerated the Android launcher/adaptive
   icons + splashes. Superseded by the icon rebrand below.
-- **B–G — pending.**
+- **B. Native web-build correctness — ✅ DONE & verified (2026-07-12).** New `ui/src/lib/origin.ts`
+  `gatewayOrigin()`; the two `location.origin` landmines fixed (`game/Game.svelte` export/share URL,
+  `screens/Wallet.svelte` site-root) — `transport.ts:32` already resolves via `VITE_GATEWAY_URL`, left
+  as-is. Service worker skipped on the native channel (`lib/pwa.svelte.ts`). Payments hidden in the MVP
+  via new `purchasesHidden()` (`lib/distribution.ts`: folds `VITE_PAYMENTS_DISABLED` + the GP flag, plus
+  a `?nopay` mock force); the `Wallet.svelte` buy tab shows a neutral pointer-free note
+  (`wallet.purchasesSoon`) for the RuStore MVP, RuStore stub kept GP-only. Native env types in
+  `vite-env.d.ts`. `svelte-check` 0 errors, `vitest` 590 passed, web + native `vite build` clean;
+  `?nopay`/`?gp` wallet states verified live via the Playwright MCP browser (the e2e runner can't fetch
+  browsers in this sandbox — the states are covered by `e2e/wallet.spec.ts`, which CI runs).
+- **C–G — pending.**
 
 Open logistics (not code): **mandatory icon rebrand (future)** — author ONE vector master and generate
 *every* icon from it (web `favicon.svg` / PWA `icon-*` / maskable, Android adaptive, future iOS). Today
@@ -232,7 +242,7 @@ is: scaffold → native-correct → gate → offline-first → CI → docs → r
 **Done when:** `npx cap sync android` succeeds against a real `pnpm build`, and (from `ui/android/`)
 `./gradlew assembleDebug` produces a debug APK that installs and cold-launches to the login screen.
 
-### B. Native web-build correctness (file:// origin)
+### B. Native web-build correctness (file:// origin) — ✅ DONE
 
 1. **One origin helper** — new `ui/src/lib/origin.ts`:
    ```ts
@@ -264,8 +274,13 @@ is: scaffold → native-correct → gate → offline-first → CI → docs → r
    }
    ```
    Switch the wallet/purchase consumers from `isGooglePlayBuild()` to `purchasesHidden()` where they
-   hide the buy actions (grep `isGooglePlayBuild` under `ui/src`). Keep the "go to RuStore" stub
-   `isGooglePlayBuild()`-only. Add `VITE_PAYMENTS_DISABLED?: string`, `VITE_STORE_URL?: string`,
+   hide the buy actions (the sole consumer is `Wallet.svelte`). Keep the "go to RuStore" stub
+   `isGooglePlayBuild()`-only. **As built (owner decision):** in the RuStore MVP (`purchasesHidden() &&
+   !isGooglePlayBuild()`) the buy tab shows a neutral, pointer-free note — new i18n key
+   `wallet.purchasesSoon`, `data-testid="purchases-hidden"` — not an empty tab and not a store link; the
+   same note can replace the RuStore stub in the later Google Play anti-steering variant.
+   `purchasesHidden()` also carries a mock-only `?nopay` force (mirrors `?gp`) so the e2e drives the
+   state without a separate build. Add `VITE_PAYMENTS_DISABLED?: string`, `VITE_STORE_URL?: string`,
    `VITE_DICT_VERSION?: string` to `ui/src/vite-env.d.ts`.
 4. **Native env matrix** — see Build & env.