Other multi-repo layouts

"Multi-repo" covers several structures, and the plugin supports one of them, git submodules, plus the single repo and monorepo it always did. The others are listed so nobody assumes they work, and so each can later become one more strategies/ file in repos.sh without touching the skills.

Layout	Shape	Status
Single repo / monorepo	One git repo, however many packages	Supported, as always
Git submodules	A workspace records each member as a gitlink	Supported (this section)
Workspace with git-ignored clones	A small workspace repo; members are independent clones at fixed paths, listed in its .gitignore	Not supported. Convert it to submodules (below), or it needs its own strategy: no gitlinks, so no landing, and the member list would need its own file
Polyrepo without a parent	Sibling repos, no repo above them	Not supported: there's no natural home for .jst/ or for the worktree's sibling layout
Manifest-based (Google repo, west, vcstool, gclient)	A manifest lists repos and revisions; a tool checks them out	Not supported. Close to submodules, but the tool owns checkouts and branches
Package-coupled polyrepo	Repos depend on each other through published versions	Not supported: merge order includes a release in between, so it's really one issue per repo
Mixed hosts	Members on GitHub and GitLab/Bitbucket	Not supported: the plugin uses gh
Fork-based contribution	PRs from a fork to an upstream the team doesn't own	Not supported

Converting a workspace of git-ignored clones to submodules

This is how the demo workspace the feature was built on was converted. Ignored files (venvs, node_modules, databases) stay where they are.

1. Check nothing can be lost. In each clone: a clean git status, no unpushed commits (git log --branches --not --remotes), no stashes, no worktrees of its own.

2. Stop ignoring the members: remove their folders from the workspace's .gitignore.

3. Adopt each clone in place. git submodule add accepts an existing repo at the path, and doesn't re-clone. Use relative URLs:

   git submodule add -b development ../app-repo.git app

4. Move each member's .git into the workspace's (.git/modules/<name>), the standard layout:

   git submodule absorbgitdirs

5. Commit and push .gitignore, .gitmodules and the new gitlinks, and update the workspace's docs: contributors now clone with --recurse-submodules.

6. Confirm that a fresh git clone --recurse-submodules rebuilds the layout. Then follow Setup.