ci: add CodeQL, lint/typecheck/smoke CI, and dependency review

- ci.yml: ruff check + format check, pyright typecheck, and import/CLI
  smoke test on Python 3.10/3.11/3.12/3.13 matrix. Uses uv like the
  existing pre-commit workflow for consistency.
- codeql.yml: weekly + push/PR Python security-and-quality analysis.
- dependency-review.yml: fail PRs adding high+ severity CVEs or copyleft
  licenses that would taint GPL-3.0 (AGPL, SSPL, BUSL).

.github/workflows/ci.yml

@@ -0,0 +1,87 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  lint:
+    name: Lint & format
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v6
+
+      - name: Install uv
+        uses: astral-sh/setup-uv@v7
+        with:
+          enable-cache: true
+          cache-dependency-glob: "uv.lock"
+
+      - name: Set up Python
+        run: uv python install 3.12
+
+      - name: Sync dependencies
+        run: uv sync --all-extras --dev
+
+      - name: ruff check
+        run: uv run ruff check .
+
+      - name: ruff format --check
+        run: uv run ruff format --check .
+
+  typecheck:
+    name: Type check (pyright)
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v6
+
+      - name: Install uv
+        uses: astral-sh/setup-uv@v7
+        with:
+          enable-cache: true
+          cache-dependency-glob: "uv.lock"
+
+      - name: Set up Python
+        run: uv python install 3.12
+
+      - name: Sync dependencies
+        run: uv sync --all-extras --dev
+
+      - name: pyright
+        run: uvx pyright@1.1.396 devgen
+
+  smoke:
+    name: Import & CLI smoke (${{ matrix.python-version }})
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ["3.10", "3.11", "3.12", "3.13"]
+    steps:
+      - uses: actions/checkout@v6
+
+      - name: Install uv
+        uses: astral-sh/setup-uv@v7
+        with:
+          enable-cache: true
+          cache-dependency-glob: "uv.lock"
+
+      - name: Set up Python ${{ matrix.python-version }}
+        run: uv python install ${{ matrix.python-version }}
+
+      - name: Sync dependencies
+        run: uv sync --all-extras --dev
+
+      - name: Import devgen
+        run: uv run python -c "import devgen, devgen.ai, devgen.utils, devgen.cli.main; print('imports OK')"
+
+      - name: CLI --help
+        run: uv run devgen --help
+
+      - name: CLI commit --help
+        run: uv run devgen commit --help