P17-T04 — Cross-platform lifecycle and privacy exit

Status: LOCAL_DONE on codex/phase-17-social-iphone-parity (phase exit task; draft PR #59 open). Issue: #58. No backend change, no migration, no existing screen redesigned, no new string resources.

Slice acceptance (frozen before coding)

• T04 (this commit) — Prove same-fixture account/social/media/ location flows through native boundaries: revoked sessions block writes without IO, ownership/erasure refusals carry fixed kinds, 24 h transient expiry and simulated-location denial hold, and diagnostics carry aliases/counts only. Tests first: shared 280/agreement vectors, revocation, erasure kinds, expiry boundary, location verdicts, no-PII diagnostics. Live transport/Keychain/background/device rows stay explicit Mac-gated limitations (never marked ready).

What changed

• application/.../feedback/FeedbackLifecycleExitTest.kt (6) — same fixtures (280/281, 6666 bp, zero-votes nil), revoked session blocks comment/vote/report with zero gateway calls, NOT_AUTHOR/COMMENT_NOT_FOUND/STALE_REVISION kinds, 24 h expiry boundary, SIMULATED/DENIED verdicts with no claim, and alias/count diagnostics without @.
• iosApp/.../FeedbackLifecycleTests.swift (6) — 1:1 XCTest transcription (280/281, 6666/nil, .signInRequired with nil op id, fixed NOT_AUTHOR/NOT_FOUND/STALE labels, TTL-1/TTL expiry, SIMULATED/DENIED denial, @-free diagnostics).
• docs/mobile/p17-t04-lifecycle-exit.md — G17 exit matrix with supported Android/JVM results and explicit Mac-gated iPhone rows; no device claim.

RED → GREEN

• RED: new tests referenced the absent exit class/vectors (Unresolved reference FeedbackLifecycleExitTest JVM-side; XCTest bodies absent Swift-side).
• GREEN (this host): ./gradlew :domain:test :application:test :data:testDebugUnitTest :app:testDebugUnitTest :app:assembleDebug BUILD SUCCESSFUL; check-mobile --static-only ok (incl. no force-unwrap); diff --check/ secrets clean. Swift build/test stays BLOCKED until Mac access (same precedent as P12-T04), never claimed.

Validation (exact commands, this host)

./gradlew :domain:test :application:test :data:testDebugUnitTest :app:testDebugUnitTest :app:assembleDebug --no-daemon
bash scripts/check-mobile.sh --static-only
git diff --check
bash scripts/scan-secrets.sh

Outcome recorded after the run below. Mac gate (BLOCKED): cd iosApp && swift build && swift test plus simulator run with synthetic-server binding and lifecycle proof (P18/G18).

Limits (not claimed)

• Swift sources are IMPLEMENTED, NOT VERIFIED (no Xcode on Linux); no swift build/test evidence is claimed here.
• No live-server, Keychain, background-outbox or device-matrix proof in this slice; G17 device rows stay open until the Mac run. Rollback: feedback flag OFF preserves existing free/offline behavior and compatible API.