Analytics, self-update and Report a problem

- Anonymous PostHog analytics (ui/frame_telemetry.py): usage on by default
  after a first-run notice; compatibility results and error details opt-in,
  offered together by the notice's "Share more to help fix problems" button.
  Random id, no person profiles or GeoIP, scrubbed text, an offline outbox,
  and "Show what's been sent" in the new Privacy panel. Inert without a
  project key, from a source checkout, or with DO_NOT_TRACK=1.
- APK installs now record install_failed when the APK itself won't install,
  and offer a 20-second test after installing. Opted-in reports reach the
  shared database through PostHog and `frame_compat_db.py sync`.
- The desktop app updates itself from published releases (app/updater.js):
  update.json from releases/latest/download, SHA-256 checked, no downgrades;
  macOS bundle swap, Windows NSIS, Linux AppImage, otherwise the release page.
  scripts/publish-release.sh publishes a tested draft with its manifest.
- Report a problem (header button, Privacy panel, Help menu) files a GitHub
  issue through the website's feedback API, with a previewed, scrubbed
  diagnostics snapshot; activity and logs only when asked for.

Reviewed by GPT-6 Astra (xhigh, read-only) three times; all findings fixed.
Docs: docs/privacy.md, docs/releasing.md.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

docs/frame-control.md

@@ -47,9 +47,11 @@ python3 ui/server.py         # anywhere: then open http://127.0.0.1:47810
   Steam library), then launch, stop, test or remove it. **Report an APK** records
   whether any APK worked (F-Droid or not: pick a file, type a package, or use an
   installed app). Your reports are saved on your computer and change the verdicts
-  you see. They aren't uploaded anywhere: the shared database is maintainer-only
-  for now (see [compat-db/README.md](../compat-db/README.md)). Uses the app's bundled
-  `adb`, or yours if you have one.
+  you see. With **Share compatibility results** on (Privacy & updates), they also
+  go to the shared database ([privacy.md](privacy.md),
+  [compat-db/README.md](../compat-db/README.md)). A failed install records
+  itself when the APK was the problem, and after an install the app offers a
+  20-second test. Uses the app's bundled `adb`, or yours if you have one.
 - **Android display**: pick a running Lepton instance (by the app in it) and set
   its resolution (Native 1920×1080, or Sharp 2560×1440 with density scaled to
   match), UI scale (Smaller / Default / Larger, or an exact dpi) and text size
@@ -139,5 +141,6 @@ npm run dist:win       # Windows: installer and .zip
 npm run dist:linux     # Linux: AppImage and .deb, x64 and arm64
 ```
 
-Pushing a `v*` tag builds all three in GitHub Actions and attaches them to the
-release (`.github/workflows/release.yml`).
+Pushing a `v*` tag builds all three in GitHub Actions and attaches them to a
+draft release (`.github/workflows/release.yml`). Running copies are offered it
+once you publish it: see [releasing.md](releasing.md).