docs(account): record step 4 (the Android screen) as built

ACCOUNT_DELETION.md §6 step 4 gains what was built beyond §4.3 (refusals
read off the body, the trust token dropped, the snackbar notice, the push
opt-in kept) and what was checked on the emulator. android/PLAN.md M8 step 3
notes the app's part is built.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E14m6SuuY6i1vASFeGDBeY

website/ACCOUNT_DELETION.md

@@ -351,6 +351,23 @@ Asked while building core (§6 step 2), the same day:
      `7bd93b8`.
    - **Not walked:** the live deletions are step 6.
 4. **Android** (`edge`): §4.3. One PR.
+   **Built 2026-10-30.** *Delete my account* is the last thing on *My account*, under a red rule,
+   and opens its own screen with the website's words. Beyond §4.3:
+   - **The refusals are read from the body.** The call reads the raw response, as the
+     trusted-device cap does, so each `code` becomes its own sentence (the web's wording).
+   - **The trust token goes too.** A sign-out keeps it for the next sign-in. A deleted account
+     has no next sign-in, so the token is dropped.
+   - **The notice** is the shell's snackbar, the one the demo's refusals use. The app opens
+     sign-in with Home beneath it.
+   - **Not touched:** the opt-in to push, which belongs to the phone, not the account. It
+     survives, as it does a sign-out.
+
+   Checked on the `s22_ultra` emulator against a local core at `7bd93b8`, with two throwaway
+   players. A wrong password showed "Your password is incorrect." The server logged one 400
+   and no replayed call, so AD12 holds in the app. Each player was deleted, one with an
+   authenticator code. The app opened sign-in with the notice, and back led to a signed-out
+   Home. The demo refusal and the no-password and last-admin refusals are covered by tests
+   only; step 6 walks them.
 5. **runicgateway.com**: §4.5, plus `PLAY_DATA_SAFETY.md` regenerated. One PR.
 6. **A walk**, using a throwaway account on each surface:
    - delete on the website, and in the app on the emulator