docs(changelog): update for v0.3.7 release

Add changelog entry summarizing additions, changes, and fixes for version v0.3.7, including improved git diff handling, test updates, and README tweaks.

CHANGELOG.md

@@ -1,3 +1,20 @@
+## [v0.3.7] - 2026-03-31
+
+Version v0.3.7: Patchin' up git diffs because exit codes shouldn't be drama queens.
+
+### Added
+- Introduce `gitDiff` variable as a mockable wrapper for `git.Diff`.
+- Introduce git.Diff function that uses CombinedOutput and treats exit code 1 as success.
+
+### Changed
+- Update tests to use `withMockGitDiff` for injecting diff mocks.
+- Tweak flag description for clarity.
+- Update prdescribe command to use git.Diff and trim whitespace when checking for empty diffs.
+- Enhance prdescribe output to include base branch in the status message.
+- Update installation and download scripts in README.md to reference v0.3.7.
+
+### Fixed
+- Improve diff handling to tolerate exit code 1.
 ## [v0.3.6] - 2026-03-30
 
 ### Fixed