ci: add PyPI publish workflow on tag v* (uses trusted publishing, no token)

.github/workflows/publish.yml

@@ -0,0 +1,56 @@
+name: publish
+
+on:
+  push:
+    tags: ["v*"]
+  workflow_dispatch:
+
+jobs:
+  build-and-publish:
+    name: build wheel + sdist and publish to PyPI
+    runs-on: ubuntu-latest
+    environment:
+      name: pypi
+      url: https://pypi.org/p/invisible-playwright
+    permissions:
+      id-token: write    # required for PyPI trusted publishing
+      contents: read
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+
+      - name: Install build deps
+        run: |
+          python -m pip install --upgrade pip
+          pip install build twine
+
+      - name: Build wheel + sdist
+        run: python -m build
+
+      - name: Check wheel has no duplicate zip entries
+        run: |
+          python - <<'EOF'
+          import zipfile, sys
+          from collections import Counter
+          from pathlib import Path
+
+          wheels = list(Path("dist").glob("*.whl"))
+          assert len(wheels) == 1, wheels
+          with zipfile.ZipFile(wheels[0]) as zf:
+              dupes = {n: c for n, c in Counter(zf.namelist()).items() if c > 1}
+          if dupes:
+              print("DUPLICATE ENTRIES IN WHEEL:", dupes)
+              sys.exit(1)
+          print("wheel is clean:", wheels[0].name)
+          EOF
+
+      - name: Validate metadata with twine
+        run: twine check dist/*
+
+      - name: Publish to PyPI
+        uses: pypa/gh-action-pypi-publish@release/v1