v0.18.1

Fixed

• git hunk list now names an unknown flag (error: unknown flag '--badflag') instead of printing the whole usage banner. parseListArgs returned a bare error where every other parser routes through the shared unknownFlag helper, so list was the only command that never told you which flag was wrong.
• zig build test ran 175 of 391 unit tests. A module's tests are discovered only if main.zig's comptime block imports it, and args.zig (175 tests, the whole CLI argument parser) and commands.zig (41) were absent — so their tests were skipped silently rather than reported. Two had rotted undetected in the meantime: one referenced a struct field that had been renamed and no longer compiled, and one freed string literals and aborted. Both fixed; all 391 now run.

Changed

• commands.zig is split from 2385 lines into three files. The result-group machinery — mapping applied hunks onto their post-apply result hashes, which is pure set arithmetic over two hunk snapshots — moves to result_groups.zig, and the temp-index commit transaction moves to commit.zig, each taking its own tests. cmdCommit stays alongside the other subcommand entry points so all nine still dispatch through one surface. No behaviour or interface change.
• Test suites share first_sha, bytes_of, blob_bytes and want_bytes from harness.sh rather than redefining them per file.