chore: import upstream snapshot with attribution

.github/workflows/README.md

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+# GitHub Actions workflows
+
+## Test All Applications (`test-all.yml`)
+
+The test workflow runs on pushes and pull requests to `main`, and can also be
+started manually. It enforces the checks that exist in the current repository:
+
+- repository tooling: template-converter tests and bundled export verification;
+- FastAPI: every pytest test using the Python version and locked dependencies
+  declared in `servers/fastapi`;
+- Next.js: all Node.js unit tests, ESLint, a production build, and Cypress
+  component tests.
+
+No test step is allowed to fail silently.
+
+## Run the CI checks locally
+
+Install Node.js 20+, npm, Python 3.11, and `uv`, then run:
+
+```bash
+./test-local.sh
+```
+
+The script installs locked dependencies and runs the same commands as the
+GitHub Actions workflow.
+
+## Run one test group
+
+### FastAPI
+
+```bash
+cd servers/fastapi
+uv sync --locked --dev
+mkdir -p /tmp/presenton-tests/app-data /tmp/presenton-tests/temp
+APP_DATA_DIRECTORY=/tmp/presenton-tests/app-data \
+TEMP_DIRECTORY=/tmp/presenton-tests/temp \
+DATABASE_URL=sqlite+aiosqlite:////tmp/presenton-tests/test.db \
+DISABLE_ANONYMOUS_TRACKING=true \
+DISABLE_IMAGE_GENERATION=true \
+uv run --locked python -m pytest --verbose --tb=short
+```
+
+### Next.js
+
+```bash
+cd servers/nextjs
+npm ci
+npm test
+npm run lint
+NEXT_PUBLIC_FAST_API=http://localhost:8000 \
+NEXT_PUBLIC_URL=http://localhost:3000 \
+npm run build
+npx cypress run --component --browser electron
+```
+
+### Repository tooling
+
+```bash
+npm ci
+npm test
+npm run sync:presentation-export
+npm run check:presentation-export
+```