Refactor CI workflows to improve efficiency and add Docker builds

.github/workflows/ci.yml

@@ -6,8 +6,15 @@ on:
   pull_request:
     branches: [main]
 
+permissions:
+  contents: read
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 jobs:
-  checks:
+  static-checks:
     runs-on: ubuntu-latest
 
     steps:
@@ -21,6 +28,12 @@ jobs:
           cache: pip
           cache-dependency-path: infra/requirements/dev.txt
 
+      - name: Cache pre-commit environments
+        uses: actions/cache@v4
+        with:
+          path: ~/.cache/pre-commit
+          key: pre-commit-${{ runner.os }}-py3.13-${{ hashFiles('.pre-commit-config.yaml') }}
+
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
@@ -35,6 +48,31 @@ jobs:
             bot \
             tests
 
+      - name: Run pre-commit
+        run: make lint
+
+  migration-heads:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6
+
+      - name: Set up Python
+        uses: actions/setup-python@v6
+        with:
+          python-version: "3.13"
+          cache: pip
+          cache-dependency-path: infra/requirements/dev.txt
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          python -m pip install -r infra/requirements/dev.txt
+
+      - name: Create CI env file
+        run: cp .env.example .env
+
       - name: Check migration HEADs
         run: |
           export PYTHONPATH="$PWD"
@@ -46,8 +84,27 @@ jobs:
             exit 1
           fi
 
-      - name: Run pre-commit
-        run: make lint
+  tests:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6
+
+      - name: Set up Python
+        uses: actions/setup-python@v6
+        with:
+          python-version: "3.13"
+          cache: pip
+          cache-dependency-path: infra/requirements/dev.txt
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          python -m pip install -r infra/requirements/dev.txt
+
+      - name: Create CI env file
+        run: cp .env.example .env
 
       - name: Run tests with coverage
         run: make test-cov
@@ -59,5 +116,13 @@ jobs:
           format: cobertura
           file: coverage.xml
 
+  docker-build:
+    runs-on: ubuntu-latest
+    needs: [static-checks, migration-heads, tests]
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6
+
       - name: Build Docker image
         run: docker build -f infra/docker/Dockerfile -t engflowbot:ci .