Adds a centralized manifest file that controls Studio update behavior,
allowing the team to temporarily switch update sources (PyPI vs git main),
control llama.cpp source/version, and notify users of critical updates --
all without requiring a PyPI release.
Changes:
- New UNSLOTH_UPDATE_DETAILS.json manifest at repo root
- setup.sh fetches manifest on startup, applies directives for unsloth
source, llama.cpp repo/tag overrides, writes install timestamp
- install_python_stack.py supports STUDIO_UNSLOTH_GIT_REF env var for
installing unsloth from git instead of PyPI
- New backend utils/update_check.py for manifest fetch and cache
- New /api/update-check endpoint in main.py (unauthenticated)
- Background thread checks manifest at startup, prints terminal banner
- New use-update-check.ts React hook (module-level cache pattern)
- navbar.tsx Update button shows dynamic badge and announcement
- __root.tsx shows non-dismissable critical update banner
