docs(changelog): note gitflow_finish arg-guard + doctor false-warn fixes under Unreleased

Historical entries describing the old "Pro session budget" framing left
intact — they record what shipped then; Keep a Changelog is append-only.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XpphkdTosUzokBDNG7PToS

CHANGELOG.md

@@ -6,6 +6,10 @@ Format follows [Keep a Changelog](https://keepachangelog.com/).
 
 ## [Unreleased]
 
+### Fixed
+- `gitflow_finish` ignored its `<type> <name>` arguments and always merged the checked-out branch — naming a different branch silently merged the wrong one. The arguments are now an optional safety assertion: if given and not equal to the current branch, `finish` refuses with a clear error instead of merging. No-argument calls (the only real caller) are unchanged.
+- `doctor.sh` false-warnings removed (a check that cries wolf is one you learn to ignore): `cargo` absence no longer claims "RTK unavailable" (RTK ships as a prebuilt binary); `check_symlink` no longer flags files reached through directory-level symlinks (e.g. `hooks/session-start.sh`); the GStack check counts the per-skill symlinks instead of a `skills/gstack` link that `link.sh` deliberately removes; the token-budget estimate is measured against the ~200k context window instead of a mis-framed "~11k session budget" that produced a false "92% CRITICAL".
+
 ## [4.0.0] — 2026-06-30
 
 ### Added