Add twine upload step to release workflow so circuitforge-core lands on
both public PyPI and the Circuit-Forge Forgejo Packages index
(--extra-index-url for cf-orch installs). Reuses FORGEJO_PYPI_TOKEN for
the release creation step. Update installation.md to document editable
install pattern and optional extras.
Add circuitforge_core.memory module: MemoryClient wraps the mnemo HTTP sidecar
for entity / relation storage. All operations no-op gracefully when sidecar is
unavailable so products can import unconditionally. Adds optional [memory]
extras entry in pyproject.toml (mnemo-sdk>=0.1.0).
