ci: add forgejo checks workflow

.forgejo/workflows/ci.yml

@@ -0,0 +1,37 @@
+name: CI
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  backend:
+    name: Backend Checks
+    runs-on: docker
+    steps:
+      - name: Check out repository
+        uses: https://data.forgejo.org/actions/checkout@v4
+
+      - name: Install uv
+        run: curl -LsSf https://astral.sh/uv/install.sh | sh
+
+      - name: Run backend quality checks
+        run: |
+          export PATH="${HOME}/.local/bin:${PATH}"
+          ./scripts/check_python_quality.sh
+
+  frontend:
+    name: Frontend Checks
+    runs-on: docker
+    steps:
+      - name: Check out repository
+        uses: https://data.forgejo.org/actions/checkout@v4
+
+      - name: Install Bun
+        run: curl -fsSL https://bun.sh/install | bash
+
+      - name: Install frontend dependencies
+        run: ${HOME}/.bun/bin/bun install --cwd frontend --frozen-lockfile
+
+      - name: Run frontend quality checks
+        run: ./scripts/check_frontend_quality.sh