chore: remove deprecated model manifests

- Remove claude-3-7-sonnet.json (deprecated/outdated)
- Remove gpt-4-5.json (deprecated/outdated)
- Cleanup obsolete model metadata

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: ericyangpan