fix-authlisted

Restore .claude.json from the most recent auto-backup when auth is corrupted. Steps: 1. Check if `~/.claude.json` exists and is valid JSON with `python -c "import json; json.load(open('C:/Users/Abix/.claude.json'))"` 2. If valid, tell the user the file is fine — no restore needed. 3. If invalid or missing, find the most recent `~/.claude/backups/.claude.json.backup.*` file (these are auto-created by Claude Code before each session). 4. Verify the backup is valid JSON too before restoring. 5. Copy the backup to `~/.claude.json`. 6. Clean up old `.corrupted.*` files from `~/.claude/backups/` (keep only the 5 most recent). 7. Tell the user to restart Claude Code.