v3.13.0: Desktop Updater, profile system fix, Antigravity E2E, conservative compaction

- Codex Desktop Updater: check/install/rollback/service management + manual rebuild
- Fix Codex CLI 0.134.0 profiles: separate <slug>.config.toml files
- Fix Antigravity: prod endpoint first, model resolution, OAUTH_PROVIDER
- Fix compaction: max_input_items 60->200 for 1M-token models
- Antigravity E2E test suite: test-antigravity.sh
- Windows GUI: UpdateDesktopWindow + profile slug fix
- Updated CHANGELOG.md and README.md

CHANGELOG.md

@@ -1,5 +1,33 @@
 # Changelog
 
+## v3.13.0 (2026-05-27)
+
+**Codex Desktop Updater, Antigravity E2E, Profile System Fix**
+
+### New Features
+- **Codex Desktop Updater**: `CodexUpdaterWindow` class — check updates, install, rollback, service management, manual rebuild from source (`ilysenko/codex-desktop-linux`)
+- **Antigravity E2E test suite**: `~/.local/bin/test-antigravity.sh` — validates token, REST endpoints, proxy adapter, model resolution
+- **Antigravity prod endpoint working**: `cloudcode-pa.googleapis.com` returns 200 with real responses for `gemini-3-flash`
+
+### Bug Fixes
+- **Fix Antigravity endpoint order**: prod (`cloudcode-pa.googleapis.com`) first, then daily-sandbox, then autopush-sandbox
+- **Fix Antigravity model resolution**: `gemini-3.5-flash-high` → `gemini-3-flash` via `_model_alias` map
+- **Fix OAUTH_PROVIDER derivation**: auto-derived from `BACKEND` env var when running without `--config`
+- **Fix `service_disabled` bail**: only returns error from prod endpoint, skips sandbox endpoints
+- **Fix compaction causing model loops**: `max_input_items: 60→200` (prod), `80→250` (sandbox); `tool_output_limit: 6000→8000`; `compaction: "aggressive"→"conservative"` — model was "forgetting" earlier reads due to aggressive compaction
+- **Fix Codex CLI 0.134.0 profile system**: profiles now written to separate `~/.codex/<slug>.config.toml` files instead of `[profiles.*]` sections in main config
+- **Fix updater false success**: checks for "successfully"/"No update ready" in output text, not return code
+
+## v3.12.1 (2026-05-27)
+
+**Fix Antigravity Adapter (PR #15)**
+
+### Bug Fixes
+- Simplified model resolution, removed broken `_sanitize_gemini_schema()`
+- Restored correct headers
+- Expanded model alias map for all Antigravity variants
+- Re-enabled gRPC fallback by default
+
 ## v3.12.0 (2026-05-27)
 
 **gRPC Auto-Fallback for Antigravity Provider (PR #13)**