refactor(git): split 2495-line git.rs into focused submodules

[BryanFRD]

Why

src/git.rs had grown to 2495 lines (1308 production + 1185 tests). One file held: low-level repo/branch helpers, all tag operations (find/create/move/list/floating/prerelease), commit walking, diff helpers, credentials + remote URL rewriting, fetch logic, the substantial push subsystem (libgit2 + shell-out workaround + rebase + retry + verification), and 63 tests.

What

Split into src/git/:

File	LOC	Contents
mod.rs	30	pub use re-exports — all external call sites unchanged
repo.rs	47	open_repo, get_repo_root, resolve_current_branch
tags.rs	357	TagMatch, find_matching_commit, is_floating_tag, is_prerelease_tag, find_last_tag/name/commit, find_highest_semver_tag, find_last_stable_tag, collect_all_tags, tag_exists, create_tag, create_or_move_tag, get_tag_message
commits.rs	135	get_commits_since_last_tag/stable_tag, signature, create_commit, create_branch_and_commit(s)
diff.rs	78	get_changed_files, get_changed_files_since_tag
auth.rs	97	extract_url_password, credentials_callback, authenticated_remote_url, get_authenticated_remote, get_remote_url
fetch.rs	19	make_fetch_options, fetch_tags
push.rs	358	force_push_tags, make_push_options, check_push_errors, verify_remote_branch, resolve_push_source, push_branch, push_tags, shell_push_tags, try_push_branch(_once), fetch_and_rebase, reset_branch_to_remote, push
retry.rs	118	retry_transient, is_transient_git_error, is_push_rejected_error
tests.rs	1183	All 63 tests, unchanged

Compatibility

All external imports (use crate::git::* in changelog, monorepo, query, status, validate) keep working untouched — verified by clean cargo check --workspace.

Verification

• cargo test --bin ferrflow → 598 passed, 0 failed
• cargo clippy --workspace --all-targets -- -D warnings → clean
• cargo fmt --check → clean

Conflict with #446 (fix/push-tags-shell-out-libgit2-revwalk-bug)

The push-tags fix branch and this refactor both touch git.rs heavily. Whichever lands first wins cheap; the second one needs a manual rebase that re-applies its edits inside the new git/ module structure. Suggested order: merge #446 first (small bug fix, urgent), then I'll rebase this PR on top of the new main.

[Copilot]

Pull request overview

Pure code-organization refactor: the 2 495-line src/git.rs is split into a src/git/ module with eight focused submodules (repo, tags, commits, diff, auth, fetch, push, retry) plus a shared tests submodule. mod.rs re-exports the previous public surface so external call sites in changelog, monorepo, query, status, and validate keep compiling unchanged. No behavior, signatures, or test bodies were modified — the 63 existing tests were moved verbatim into src/git/tests.rs.

Changes:

• Split src/git.rs into per-concern submodules under src/git/ (auth, commits, diff, fetch, push, repo, retry, tags).
• Preserve the existing public API via pub use re-exports in mod.rs; tighten visibility of internal helpers to pub(super).
• Move all 63 tests into a single tests submodule that pulls helpers via super::* and module-specific use paths.

Reviewed changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/git.rs	Deleted; content distributed across the new src/git/ submodules.
src/git/mod.rs	New module root, declares submodules and re-exports the previous public API.
src/git/repo.rs	open_repo, get_repo_root, resolve_current_branch extracted.
src/git/tags.rs	All tag query/create/move helpers, TagMatch, floating/prerelease classifiers.
src/git/commits.rs	Commit walking, signature, single/multi-commit creators; re-exports GitLog.
src/git/diff.rs	get_changed_files and get_changed_files_since_tag.
src/git/auth.rs	URL credential parsing, libgit2 credentials callback, authenticated remote helpers.
src/git/fetch.rs	make_fetch_options and fetch_tags.
src/git/push.rs	Full push subsystem: shell-out tag push, branch push w/ retry, rebase, reset, verify.
src/git/retry.rs	Generic transient retry loop, is_transient_git_error, is_push_rejected_error.
src/git/tests.rs	All 63 tests moved verbatim; imports adjusted for the new module paths.

[github-actions]

Benchmark

Details

Benchmark suite	Current: 9f692fb	Previous: 0b5fe57	Ratio
version_files/toml_read	9484 ns/iter (± 126)	8489 ns/iter (± 791)	1.12
version_files/toml_write	127933 ns/iter (± 10741)	132036 ns/iter (± 10286)	0.97
version_files/json_read	6352 ns/iter (± 62)	5314 ns/iter (± 69)	1.20
version_files/json_write	97870 ns/iter (± 10319)	130851 ns/iter (± 8755)	0.75
version_files/xml_read	5862 ns/iter (± 47)	5140 ns/iter (± 16)	1.14
version_files/xml_write	100463 ns/iter (± 17010)	138826 ns/iter (± 18123)	0.72
version_files/gradle_read	5773 ns/iter (± 48)	4981 ns/iter (± 37)	1.16
version_files/gradle_write	97806 ns/iter (± 7688)	128857 ns/iter (± 12186)	0.76

This comment was automatically generated by workflow using github-action-benchmark.