fix: remove docs/plans and add to .gitignore (#2698)

- Delete docs/plans directory
- Add docs/plans to .gitignore to prevent tracking

Author: malek10xdev

.gitignore

@@ -21,3 +21,4 @@ supabase/config.toml
 frontend-v4/*
 .worktrees/
 .opencode/plans/
+docs/plans/