Garden package ties manifest and store together. Supports adding
files (hashed and stored as blobs), directories (manifest-only),
and symlinks (target recorded). Paths under $HOME are stored as
~/... in the manifest for portability. CLI init and add commands
wired up via cobra.
8 tests covering init, open, add for all three entry types,
duplicate rejection, HashFile, and tilde path expansion.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
