build(release): a Dart release tool for every app

tool/release.dart releases one app: `dart run tool/release.dart learn
[major | minor | patch] [--dry-run]`, each app configured in Dart beside
it (apps/learn/release.dart). Every step and check of tool/release.sh
is kept: the repository as pushed, resuming after a release commit and
tag, Flutter as CI pins it, the tools, the key and its certificate pin,
secrets asked for without echo and never written down, CI green on the
newest commit, the signed release commit and tag by a key deploys
accept, the APK built from a checkout of the tag and checked, the snap,
the signed checksums, pushing only after both builds passed, the
release on Forgejo, the F-Droid repository, the Snap Store once a
channel is set.

New: tags per app (learn-v0.19.0, Learn's v… counting as its
history); only commits touching the app decide its version (its folder,
the shared packages it uses by path, the root pubspec and lock, its
release files, where its packages were before the move); --dry-run
reads all of it, lists every step and the notes, and what a release
would refuse, changing nothing. The pure parts are tested in
test/release/. Learn releases build 21 with tool/release.sh, then
switches.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

AGENTS.md

@@ -79,7 +79,7 @@ Checklist after doing changes, in this order:
 - Check `serverpod` MCP `tail_server_logs` and `tail_flutter_logs` for any issues.
 
 - **Melos** (decided 2026-10-19, ADR 0015) runs scripts across the workspace's packages: a dev dependency of the root (`dart run melos …`, its version in the lock), its scripts under `melos:` in the root `pubspec.yaml`: `analyze`; `test:dart` (the packages without Flutter, one at a time, as each server's tests start a PostgreSQL of their own on the same port); `test:flutter` (`flutter test -x requires-server`, one package at a time); `generate` (Serverpod's code generation in every package with a `config/generator.yaml`, the CLI on the PATH); `check` (`tool/check.dart`). Every script takes Melos' filters: `dart run melos run test:flutter --scope=halkyon_app`, or `--diff=origin/main --include-dependents` for what changed and what depends on it; `dart run melos list` lists the packages. The root overrides `cli_util` to 0.5.2 for it: Learn's `flutter_launcher_icons` (0.14.4, its latest) asks for ^0.4.1 and uses only the logger, which 0.5 keeps; drop the override once that package allows 0.5.
-- **Tools are Dart where they hold logic** (decided 2026-10-19): conditions, parsing, parallel work, anything worth a test, as `tool/check.dart` (its file selection in `tool/src/check_files.dart`, tested in the root's `test/`). **Bash for glue**, short and linear (`tool/pre-push`, `tool/check_signatures.sh`, `tool/workspace_only.sh`, which narrows the root pubspec's workspace to the packages an image builds), **and for everything run on the production host**, which has no Dart SDK and gets none (`deploy/redeploy.sh`, `deploy/backup.sh`). **Python only where a library exists only there** (Learn's icons with Pillow, its Anki fixtures with Anki itself); Learn's data scripts and `packages/halkyon_app/tool/subdivision_names.py` need nothing but Python's standard library and may move to Dart when they next change. `tool/release.sh` and `tool/fdroid_repo.sh` are Learn's release, in Bash until build 21 is out; then a release tool in Dart, shared by the apps, takes over (ADR 0015).
+- **Tools are Dart where they hold logic** (decided 2026-10-19): conditions, parsing, parallel work, anything worth a test, as `tool/check.dart` (its file selection in `tool/src/check_files.dart`, tested in the root's `test/`). **Bash for glue**, short and linear (`tool/pre-push`, `tool/check_signatures.sh`, `tool/workspace_only.sh`, which narrows the root pubspec's workspace to the packages an image builds), **and for everything run on the production host**, which has no Dart SDK and gets none (`deploy/redeploy.sh`, `deploy/backup.sh`). **Python only where a library exists only there** (Learn's icons with Pillow, its Anki fixtures with Anki itself); Learn's data scripts and `packages/halkyon_app/tool/subdivision_names.py` need nothing but Python's standard library and may move to Dart when they next change. **Releases come from `tool/release.dart`** (decided 2026-10-19, ADR 0015), shared by the apps, each configured in Dart beside it (`apps/<id>/release.dart`, typed and commented, registered in `tool/src/release/apps.dart`): `dart run tool/release.dart learn [major | minor | patch] [--dry-run]`, on a developer's laptop, never in CI. Tags are per app (`learn-v0.19.0`; an app's earlier tags, Learn's `v…`, count as its history), and only commits touching the app decide its version: its folder, the shared packages its packages use by path (transitively), the root pubspec and lock, its release files (key pins, F-Droid listing, snap recipe) and where its packages were before a move. `--dry-run` reads everything a release would (the version, the commits that count and what each touches, the steps, the notes it would publish), changes nothing, asks for no secret, and lists what a release would refuse. Its pure logic is in `tool/src/release/`, tested in the root's `test/release/`. `tool/fdroid_repo.sh` stays Bash (glue for fdroidserver). `tool/release.sh` releases build 21 alone, the release going with ADR 0014's breaking deploy, by the script it was proven with; then it goes.
 
 ## CI and deploys