ci: add lint/test/validate workflow; fix stale fedora-cloud-42 label -> fedora

.gitea/workflows/build-iso.yaml

@@ -28,7 +28,7 @@ jobs:
   
   build-iso:
     needs: validate
-    runs-on: fedora-cloud-42
+    runs-on: fedora
     container:
       image: git.phyllo.me/devops/fedora-runner-image:latest
     

.gitea/workflows/ci.yml

@@ -0,0 +1,25 @@
+name: ci
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  # Bump when the recipe language changes; both jobs share the runner.
+  cook:
+    runs-on: fedora
+    defaults:
+      run:
+        shell: bash
+    container:
+      image: git.phyllo.me/devops/fedora-runner-image:latest
+    steps:
+      - uses: https://git.phyllo.me/devops/checkout@v5
+        with:
+          fetch-depth: 0
+      - name: Lint manifest + templates
+        run: make -C cook lint
+      - name: Generate recipes + dishes, validate every dish
+        run: make -C cook all
+      - name: Run the pytest suite
+        run: make -C cook test