Move the canonical forge to Codeberg, and add Renovate + Weblate (#2)

Makes Codeberg canonical for git, issues, PRs, tags and releases. The self-hosted Gitea instance stays build infrastructure: signing key, F-Droid publishing, release pipeline. Ports the setup Calendula already runs on, adapted where Agendula genuinely differs.

**This PR is its own test.** It is the first PR opened on Codeberg, so a green `CI` check proves the new runner works *and* that the submodule resolves from its new home.

### 1 · Workflows split by directory

Forgejo's lookup is first-match-wins across `.forgejo/` → `.gitea/` → `.github/`, and Gitea cannot see `.forgejo/` at all. So each forge sees exactly one set, with no duplicated files and no expression to keep in sync:

| Directory | Runs on | Contains | Secrets |
| --- | --- | --- | --- |
| `.forgejo/workflows/` | Codeberg | `ci.yaml`, `translations.yaml` | **none** |
| `.gitea/workflows/` | Gitea | `release.yaml`, `renovate.yml` | all of them |

The line is drawn at **secrets, not CI-vs-release** — that is what makes fork PRs safe. Renovate deliberately does *not* move despite opening PRs here; it keeps running where its token already lives and merely talks to Codeberg's API.

CI also gains three fixes: an explicit `SKIP_RE` skip-list that names the build-relevant files in the log, base-ref normalisation, and a fully-qualified `android-actions/setup-android` — Codeberg resolves bare `uses:` refs against `data.forgejo.org`, which does not carry that action.

### 2 · Three release-pipeline safety changes

- `detect` and the Renovate job get an explicit `repository_owner` guard. The directory split only holds while `.forgejo/` is non-empty; empty it and Codeberg would fall back to `.gitea/` and start running these on the contributor-facing runner, without secrets.
- `detect` now reads tags from **Codeberg**, not from the Gitea instance it runs on. Push mirroring is `git push --mirror`, so a tag minted on Gitea is deleted by the next sync until the Codeberg tag push propagates back — asking Gitea inside that window reports "no tag" for an already-shipped release and would cut it twice. It also now fails on any status other than 200/404 rather than reading a transient error as "no tag": a failed job is recoverable, a duplicate release is not.
- **The Codeberg publish step pushes the tag itself** instead of waiting for it to arrive by mirror. That wait was correct while Gitea mirrored *to* Codeberg; under Codeberg-canonical the mirror runs the other way and it would never resolve. Attaching the release to an already-pushed ref (no `target_commitish`) is what avoids the empty-bodied 500s, and the create call retries with backoff because Codeberg 500s on a tag it has only just received. The step stays **fail-loud**, not `continue-on-error` — it reported green through 0.2.1–0.3.2 while never once publishing, and that must not be possible again.

### 3 · Renovate

`renovate.json5` plus a Gitea-side job targeting Codeberg's API. `managerFilePatterns` covers **both** workflow directories, so the pinned Renovate image tag and the action versions in either file keep getting bumped.

Needs two new Gitea secrets: `RENOVATE_TOKEN` (Codeberg bot, repo read/write + PR scope) and `GITHUB_COM_TOKEN` (read-only github.com PAT, for changelog lookups).

### 4 · Weblate

A parity check (`scripts/check_translations.py`) runs on every PR without a path filter, so the required `Translations` status is always reported. Partial translations are expected, so `MissingTranslation` and `MissingQuantity` become informational — `ExtraTranslation` stays fatal. Agendula had no `lint` block at all, so the first locale to land would otherwise have failed the build.

**Settings → App language** now opens a picker carrying a "Help translate" header. That is why it drops floret-kit's `LanguagePickerRow` for a local row: the shared recipe has no `header` slot, and the framing is app-specific rather than a family primitive.

### 5 · Links repointed

In-app Source / License / report-issue URLs, F-Droid metadata, README (now with a Codeberg CI badge), and the docs.

`floret-kit` follows suit — `.gitmodules` points at `codeberg.org/jlmakiola/floret-kit`, so a clone no longer needs to reach the personal Gitea instance to resolve it. The Gitea copy is **kept**: every existing tag records the old submodule URL, so rebuilds of past releases still resolve.

### 6 · Housekeeping

Drops `release-notes.md` — a release-pipeline scratch file that got committed — and gitignores the five others the release job writes into the workspace.

### Not in this PR

The Codeberg → Gitea push mirror, the Weblate component, and the Codeberg bot account (all browser-side). Until the mirror is flipped, merging this does **not** reach the Gitea runner.

Co-authored-by: Jean-Luc Makiola <business@jeanlucmakiola.de>
Reviewed-on: https://codeberg.org/jlmakiola/agendula/pulls/2

fdroid-metadata/de.jeanlucmakiola.agendula.yml

@@ -6,5 +6,5 @@ Summary: A modern Material 3 Expressive task app for Android.
 Categories:
   - Time
 
-SourceCode: https://gitea.jeanlucmakiola.de/makiolaj/agendula
-IssueTracker: https://gitea.jeanlucmakiola.de/makiolaj/agendula/issues
+SourceCode: https://codeberg.org/jlmakiola/agendula
+IssueTracker: https://codeberg.org/jlmakiola/agendula/issues