ci: build against bread-ecosystem's shared Arch CI image, add check.yml

Same fix as breadpad: build inside the shared pinned Arch container
(bread-ecosystem/ci/, cloned at the sha in ci/bread-ecosystem.rev)
instead of building natively against whatever's on the runner host.
Adds check.yml (clippy + test on feature/**/fix/**) as a fast-fail gate
before anything reaches main.

Verified locally: build, clippy, and test all pass through the new
container path — no pre-existing lint/test debt found here.

.forgejo/workflows/dev-release.yml

@@ -19,7 +19,7 @@ jobs:
             "https://git.breadway.dev/${GITHUB_REPOSITORY}.git" src
 
       - name: build
-        run: cd src && cargo build --release --locked
+        run: cd src && bash ci/build.sh cargo build --release --locked
 
       - name: compute dev version
         run: |