agents: add conversation-done skill

.agents/skills/conversation-done/SKILL.md

@@ -0,0 +1,95 @@
+---
+name: conversation-done
+description: >-
+  Clean up files and resources that aren't part of the agent conversation
+  (e.g. Bazel output base, Git worktree, local/remote branches)
+---
+
+# Conversation Done Skill
+
+Cleans up external workspace resources created during agent workflows while
+preserving agent conversation data, chat history, and brain transcripts.
+
+## Overview
+
+When agents work on tasks, several external resources outside the agent
+conversation directory (`~/.gemini/jetski/brain/`) are created:
+
+1. **Bazel Output Base(s)**: Intermediate build artifacts, execroot trees,
+   and running Bazel server and persistent worker processes (consuming tens of
+   gigabytes of disk and substantial RAM).
+2. **Git Worktree**: The checked-out directory on disk.
+3. **Local Git Branch**: The feature branch associated with the worktree.
+4. **Remote Git Branch**: The feature branch pushed to the user's fork
+   (e.g., `origin`).
+
+This skill safely shuts down active build processes and reclaims these
+resources without removing the conversation transcript or chat history.
+
+## Script Location
+
+The cleanup script is located at:
+`./.agents/skills/conversation-done/scripts/cleanup.py`
+
+## Usage
+
+### 1. Clean Up Current Workspace
+
+When invoked from within the agent's worktree:
+
+```bash
+# Preview what would be removed:
+./.agents/skills/conversation-done/scripts/cleanup.py --dry-run
+
+# Clean up resources (interactive confirmation if TTY):
+./.agents/skills/conversation-done/scripts/cleanup.py
+
+# Force cleanup non-interactively (ideal for agents/scripts):
+./.agents/skills/conversation-done/scripts/cleanup.py --force
+```
+
+### 2. Clean Up by Worktree Path or Branches
+
+```bash
+# By worktree path:
+./.agents/skills/conversation-done/scripts/cleanup.py \
+  --worktree /path/to/worktree --force
+
+# By branch name:
+./.agents/skills/conversation-done/scripts/cleanup.py \
+  --branches my-feature-branch --force
+
+# By multiple branches:
+./.agents/skills/conversation-done/scripts/cleanup.py \
+  --branches branch-one branch-two --force
+```
+
+### 3. Inspect Active Resources
+
+List all worktrees, branches, and Bazel output bases:
+
+```bash
+./.agents/skills/conversation-done/scripts/cleanup.py --list
+```
+
+## Selective Cleanup Flags
+
+Fine-tune what gets cleaned up using selective leave flags:
+
+* `--leave-bazel-output-base`: Leave Bazel output bases and build caches
+  intact.
+* `--leave-worktree`: Leave Git worktree directory on disk.
+* `--leave-branch`: Keep local Git branch.
+* `--leave-remote`: Do not delete branch from remote fork.
+* `--remote <name>`: Override remote destination (default: `pushRemote` or
+  `origin`).
+
+## Safety Guarantees
+
+* **Main Repository Protection**: Never removes the primary Git repository
+  worktree.
+* **Protected Branches**: Never deletes `main`, `master`, `release/*`, or
+  `HEAD`.
+* **Upstream Remote Protection**: Never deletes branches on `upstream`.
+* **No Expunge Rule**: Never runs `bazel clean --expunge`; shuts down servers
+  gracefully and deletes the specific output base directory directly.