fix: preserve database compatibility and harden request lifecycles

.github/workflows/ci.yml

@@ -40,6 +40,39 @@ jobs:
       - name: go test
         run: go test ./...
 
+  database-compatibility:
+    name: SQLite / PostgreSQL ${{ matrix.postgres }}
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        postgres: [16, 17]
+    services:
+      postgres:
+        image: postgres:${{ matrix.postgres }}-alpine
+        env:
+          POSTGRES_USER: mebox
+          POSTGRES_PASSWORD: mebox-test-only
+          POSTGRES_DB: mebox_test
+        ports:
+          - 5432:5432
+        options: >-
+          --health-cmd "pg_isready -U mebox -d mebox_test"
+          --health-interval 5s
+          --health-timeout 5s
+          --health-retries 10
+    env:
+      MEBOX_TEST_POSTGRES_DSN: postgres://mebox:mebox-test-only@127.0.0.1:5432/mebox_test?sslmode=disable
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-go@v5
+        with:
+          go-version: '1.26'
+          cache: true
+
+      - name: Database regression tests
+        run: go test ./internal/database ./internal/repository -count=1
+
   frontend:
     name: Frontend (Node)
     runs-on: ubuntu-latest
@@ -78,7 +111,7 @@ jobs:
   ci-success:
     name: CI Success
     runs-on: ubuntu-latest
-    needs: [backend, frontend, smoke]
+    needs: [backend, frontend, database-compatibility, smoke]
     if: success()
     steps:
       - run: echo "CI passed, ready for release"