Merge pull request 'Worktrees die with their cut' (#26) from eureka-self/worktree-retention into main

SKILL.md

@@ -691,6 +691,14 @@ Scripts that know a project's layout stay in that project.
   that verifies and fixes mechanical adaptations only.
 - **Pin sibling checkouts with a guard that checks revision and cleanliness.**
   Scope the guard to projects that actually reference the sibling.
+- **Self removes a cut's worktrees in the turn the cut merges or is abandoned,**
+  Unity copies and job and probe directories included. Before removing one,
+  park any head no ref contains under a local `keep/<name>` tag. Never defer
+  cleanup to a handoff. On 2026-10-23 `C:\aeth-wt` held 255 GB of
+  merged-cut worktrees that a handoff had put off "until idle". C: fell to
+  1.4 GB free during an operator flight, and a new checkout died mid-write.
+  Operator: "you really gotta start cleaning up after yourself". Check free
+  space before creating a worktree.
 
 ## Adapting the pipeline
 

references/changelog.md

@@ -2,6 +2,14 @@
 
 Record each change to the skill together with the evidence that motivated it.
 
+## 2026-10-23: worktrees die with their cut
+
+Self, session `self-2026-10-23-ag8`.
+
+Evidence. `C:\aeth-wt` held 255 GB, mostly 1.7-3.9 GB Unity worktrees from sessions ag3 to ag7. The ag7 handoff listed them as "worktrees to remove when idle". C: was at 1.4 GB free while the operator flew, and a new worktree checkout failed mid-write. A two-pass sweep removed about 140 worktrees and directories. Operator: "you really gotta start cleaning up after yourself".
+
+What changed. `SKILL.md` git and tooling rules: Self removes a cut's worktrees in the turn the cut merges or is abandoned, parks unreferenced heads under `keep/` tags first, and checks free space before creating a worktree.
+
 ## 2026-10-14: nothing that exists is sacred, her words included
 
 Self, session `self-2026-10-14-ag`.