Restore the git-rebase skill 1:1 with GaaS

Replace the intern-recipe rewrite with Guy's GaaS body, including /tmp editor scripts. Keep user-invocable: false so the skill stays use_skill-only. Intern execution stays on native-integration. Clarify that Linear claim-first owns the In Review write, not GitHub review posting.

Author: TheGreatAxios

CHANGELOG.md

@@ -20,6 +20,7 @@ parallel copies under `docs/` or `scripts/notes/`. At cut time: rename
 ### Changed
 
 - Drop unused `@opentui/keymap`, `@opentui/solid`, and `solid-js`. The interactive TUI is imperative `@opentui/core` only.
+- Restore the git-rebase skill body 1:1 with GaaS. Intern execution recipe stays on native-integration. user-invocable: false stays so it remains use_skill-only.
 - Restore the linear-issue-workflow skill body 1:1 with GaaS. Claim-first, In Review, and git-worktrees extras stay on native-integration. user-invocable: false stays so it remains use_skill-only.
 - Restore the interview skill body 1:1 with GaaS (AskUserQuestion). Operator-ask mapping stays on native-integration. Slash /interview remains.
 - Restore the implement skill body 1:1 with GaaS (TaskCreate, @greybeard, Acknowledgment). Tool-name mapping stays on native-integration. Slash /implement remains.