Partial Clone

Note	Draft placeholder — outline notes only; prose not yet written.

Points this section needs to cover:

Object filters: git clone --filter=blob:none (blobless) and --filter=tree:0 (treeless); when to use each
Promisor remotes and lazy, on-demand object fetching
git backfill (experimental) for batch-downloading missing blobs
Full history for log; which operations trigger network fetches
Why partial clone usually beats shallow clone for day-to-day work
Pointer to the internals story (promised objects) in Ch 10, Git Internals