fix(list): load settings from primary worktree, not cwd

[acreeger]

Summary

• Bug: il list from a child worktree with settings.local.json overriding mainBranch showed only worktrees without metadata (e.g., develop and develop-react), filtering out all registered looms
• Root cause: findMainWorktreePathWithSettings() loaded settings from process.cwd(), picking up the child worktree's local override, resolving currentProjectPath to the wrong worktree
• Fix: Load settings from the primary git worktree (first in porcelain output) so project path resolution is consistent regardless of which worktree you're in

Test plan

• il list from a child worktree with mainBranch override in settings.local.json now shows all looms
• il list from the main worktree still works correctly