Feature request: git commit indexing for a workspace folder that contains several repos #747

What happened?

Magic Context: 0.49.13 (unchanged in 0.49.15).

My main workspace is a plain folder that holds several git repos:

workspace/          ← sessions start here; not a git repo
  service-a/        ← repo
  service-b/        ← repo
  service-c/        ← repo
  … (9 repos in total)

memory.git_commit_indexing only indexes the session folder's own HEAD, and indexCommitsForProject returns nonIndexable for not_a_repo. Commit search therefore never finds anything here, although the folder holds plenty of history. Starting sessions inside each repo isn't practical, since the work spans several of them.

Would you consider indexing the immediate child repos when the session folder isn't itself a repo? For example:

• Opt in, e.g. git_commit_indexing.nested_repos: true or a list of paths.
• Limit to one level deep, and skip node_modules and similar.
• Results labelled with the repo name, so ctx_search hits say which repo a commit came from.
• The existing since_days / max_commits caps applied per repo, or across all of them.

Related: a session rooted in any non-git folder gets a dir: identity, so commit search is always empty there, and the git sweep still logs [git-commits] sweep skipped for dir:… cooldown active on every 15-minute tick for such projects (467 lines in 1.3 days here). plugin/dream-timer.ts:834-841 logs on every cooldown_active, although :853-858 parks dir: projects for 24 h. Logging once per park, and skipping dir: identities before calling git log, would remove that noise. Closest existing issues: #555, #717.

If nested indexing doesn't fit the design, for example because mixing commits from unrelated repos would hurt search quality, that's an understandable no. I wanted to check whether a folder-of-repos layout is something you'd support.