feat: check formatting, linting and tests in CI

Every push runs ruff, prettier, pytest and svelte-check; a tagged release runs the
blocking half again before it publishes an image. eslint and svelte-check report
without failing, since 87 and 30 findings predate the workflow.

AGENTS.md

@@ -103,6 +103,11 @@ API docs are served by the running backend at `http://localhost:8000/schema/` (S
   manually against a live backend).
 - **Migrations are mandatory.** The app runs with `create_all=False`, so a model change without a
   matching Alembic revision will not reach the database.
+- **CI gates formatting, linting and tests.** `.gitea/workflows/ci.yml` runs on every push and pull
+  request: `ruff format --check`, `ruff check`, `pytest`, and `prettier --check` all **block**;
+  `eslint` and `pnpm check` report without failing until their pre-existing counts reach zero. A
+  `v*` tag additionally builds and publishes both container images — see
+  `docs/ci-release-pipeline.md`.
 - **Commit messages** follow `type: summary` — `feat:`, `fix:`, `refactor:`, `chore:`.
 - The three `README.md` files are user-facing. Agent-facing knowledge belongs in the `AGENTS.md`
   files.