docs: add OAuth re-auth instructions to CLAUDE.md #3
Description
Problem
When account tokens expire/get revoked, there's no quick reference for how to re-authenticate. Had to dig through the codebase to find the command.
Solution
Add to CLAUDE.md:
## Re-authenticating accounts
When an account token expires:
```bash
./gsuite-mcp auth
This opens a browser for Google OAuth. Run once per account that needs re-auth. To check which accounts are authenticated:
./gsuite-mcp accounts
## Context
Tokens for `live2dive77@gmail.com` and `ali.watters@pcc.edu` both expired during a session and required re-auth. The command wasn't documented anywhere obvious.