Update internal/jupyter/workspace_metadata.go to use centralized PathRegistry:
Changes:
- Add import for internal/config package
- Update saveMetadata() to use config.FromEnv() for directory creation
- Replace os.MkdirAll with paths.EnsureDir() for metadata directory
Benefits:
- Consistent directory creation via PathRegistry
- Centralized path management for workspace metadata
- Better error handling for directory creation
- Move ci-test.sh and setup.sh to scripts/
- Trim docs/src/zig-cli.md to current structure
- Replace hardcoded secrets with placeholders in configs
- Update .gitignore to block .env*, secrets/, keys, build artifacts
- Slim README.md to reflect current CLI/TUI split
- Add cleanup trap to ci-test.sh
- Ensure no secrets are committed