chore: .claude/settings.local.json is tracked in git — personal local settings with machine-specific paths and a broad home-read allow #370

Problem

.claude/settings.local.json is tracked in git. By name and by Claude Code convention it is the local (personal, per-machine) settings file — the shared project file is settings.json. This is the only file under .claude/ in the repo, and .gitignore does not cover it (git check-ignore .claude/settings.local.json reports NOT-IGNORED; verified on main 2b0c539b).

Evidence (main 2b0c539b)

• git ls-files .claude/ returns exactly one file: .claude/settings.local.json (917 bytes).
• Its contents are one machine's personal permission allowlist, e.g.:
  • Read(//home/user/**) — a blanket read of another home directory
  • Read(//home/user/.claude/**), Read(//home/user/.config/openchamber/**), Read(//tmp/cc-extract/package/dist/**)
  • One-off Bash(...) allows naming files from a different checkout layout (home/common/default.nix, nixos/services/cloudflared/default.nix)
• .gitignore ignores the analogous local override .env.local (line 104) but has no entry for .claude/settings.local.json.

Every clone therefore inherits a personal allowlist that (a) does nothing useful on any other machine (the /home/user/... paths are not this repo's layout), and (b) normalizes committing local agent settings — the next person's settings.local.json may carry broader or more sensitive allows.

Why it matters

Local settings files are the agent-tooling equivalent of .env.local: personal, machine-specific, and a standing invitation to leak local paths/permissions into a shared repo. The repo already untracked the same class of artifact in .opencode/ (#367, filed-only) and pkgs/launcher's binary (#353); this is the remaining *.local.* settings file still tracked.

Acceptance criteria

• .claude/settings.local.json is no longer tracked (git ls-files .claude/ is empty, or only a deliberate shared settings.json remains).
• .gitignore gains .claude/settings.local.json so it cannot be re-committed accidentally (git check-ignore matches).
• If any of the allows are genuinely meant to be shared project permissions, they are moved to a new .claude/settings.json with repo-relative paths instead of /home/user/... absolutes; otherwise no replacement is needed.
• No other file changes; the local file may remain on disk for its owner (untrack, do not necessarily delete content from history — history rewrite is out of scope).

Suggested fix

git rm --cached .claude/settings.local.json (or delete in the PR if the content is not needed) plus one .gitignore line — a small, low-risk change in the same class as #353/#355/#363.