* feat: smart force-push protection with backup strategies (#187)
Replace blunt `backupBeforeSync` boolean with `backupStrategy` enum
offering four modes: disabled, always, on-force-push (default), and
block-on-force-push. This dramatically reduces backup storage for large
mirror collections by only creating snapshots when force-pushes are
actually detected.
Detection works by comparing branch SHAs between Gitea and GitHub APIs
before each sync — no git cloning required. Fail-open design ensures
detection errors never block sync.
Key changes:
- Add force-push detection module (branch SHA comparison via APIs)
- Add backup strategy resolver with backward-compat migration
- Add pending-approval repo status with approve/dismiss UI + API
- Add block-on-force-push mode requiring manual approval
- Fix checkAncestry to only treat 404 as confirmed force-push
(transient errors skip branch instead of false-positive blocking)
- Fix approve-sync to bypass detection gate (skipForcePushDetection)
- Fix backup execution to not be hard-gated by deprecated flag
- Persist backupStrategy through config-mapper round-trip
* fix: resolve four bugs in smart force-push protection
P0: Approve flow re-blocks itself — approve-sync now calls
syncGiteaRepoEnhanced with skipForcePushDetection: true so the
detection+block gate is bypassed on approved syncs.
P1: backupStrategy not persisted — added to both directions of the
config-mapper. Don't inject a default in the mapper; let
resolveBackupStrategy handle fallback so legacy backupBeforeSync
still works for E2E tests and existing configs.
P1: Backup hard-gated by deprecated backupBeforeSync — added force
flag to createPreSyncBundleBackup; strategy-driven callers and
approve-sync pass force: true to bypass the legacy guard.
P1: checkAncestry false positives — now only returns false for
404/422 (confirmed force-push). Transient errors (rate limits, 500s)
are rethrown so detectForcePush skips that branch (fail-open).
* test(e2e): migrate backup tests from backupBeforeSync to backupStrategy
Update E2E tests to use the new backupStrategy enum ("always",
"disabled") instead of the deprecated backupBeforeSync boolean.
* docs: add backup strategy UI screenshot
* refactor(ui): move Destructive Update Protection to GitHub config tab
Relocates the backup strategy section from GiteaConfigForm to
GitHubConfigForm since it protects against GitHub-side force-pushes.
Adds ShieldAlert icon to match other section header patterns.
* docs: add force-push protection documentation and Beta badge
Add docs/FORCE_PUSH_PROTECTION.md covering detection mechanism,
backup strategies, API usage, and troubleshooting. Link it from
README features list and support section. Mark the feature as Beta
in the UI with an outline badge.
* fix(ui): match Beta badge style to Git LFS badge
