fix(#370): add Gitea PyPI registry to coordinator CI install step

The mosaicstack-telemetry package is hosted on the Gitea PyPI registry.
CI pip install needs --extra-index-url to find it.

Refs #370

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.woodpecker/coordinator.yml

@@ -30,7 +30,7 @@ steps:
       - python -m venv venv
       - . venv/bin/activate
       - pip install --no-cache-dir --upgrade "pip>=25.3"
-      - pip install --no-cache-dir -e ".[dev]"
+      - pip install --no-cache-dir --extra-index-url https://git.mosaicstack.dev/api/packages/mosaic/pypi/simple/ -e ".[dev]"
       - pip install --no-cache-dir bandit pip-audit
 
   ruff-check: