fix/cleanup-lfs

[bwalsh]

6) Deprecation Candidates

These are candidates for cleanup/refactor, based on current behavior and code layout.

6.1 Outdated / legacy LFS-oriented paths

• cmd/fetch/main.go still shells out to git lfs pull directly. This is a legacy-style path compared with the managed DRS pull path in cmd/pull/main.go.
• cmd/pull/main.go long help string says "git pull, git lfs pull, git lfs checkout", but implementation now uses DRS checksum lookup + direct download + git lfs checkout fallback. The wording is partially stale.

Candidate action:

• Decide whether git drs fetch should be kept as an explicit LFS compatibility command, or deprecated in favor of git drs pull + git drs query workflows.
• Update command docs/help text to avoid implying git lfs pull is always used in git drs pull.

6.2 Duplicated logic

• Download option constants are duplicated:
  • internal/drsremote/remote.go (DownloadResolvedToPath via downloadResolved)
  • cmd/download/main.go (same MultipartThreshold, Concurrency, ChunkSize values).
• Branch/ref parsing logic is duplicated in cmd/prepush/main.go:
  • readPushedRefs(...) + branchesFromRefs(...)
  • readPushedBranches(...) (older equivalent helper)

Candidate action:

• Centralize transfer defaults into one constant/config source.
• Keep one branch parsing path in pre-push and remove the duplicate helper after test updates.

6.3 Low-value / effectively unused runtime code paths

• readPushedBranches(...) in cmd/prepush/main.go is not used by production pre-push flow (the flow uses readPushedRefs + branchesFromRefs), and appears retained mainly for tests (cmd/prepush/main_test.go).

Candidate action:

• Replace test usage with readPushedRefs + branchesFromRefs, then remove readPushedBranches.

6.4 Documentation-level deprecation candidates

• Any docs that describe git drs fetch as metadata-only should be revalidated against implementation (cmd/fetch/main.go currently performs git lfs pull).
• Any docs that describe git drs pull as an unconditional "git lfs pull" wrapper should be updated to reflect the DRS-driven download path.

[matthewpeterkort]

addressed in #232