Authorization
Context7 should mirror `websearch` by only sending auth when `CONTEXT7_API_KEY` is set. Change: set bearer auth in `headers` using `CONTEXT7_API_KEY` if said environment variable is set, otherwise leave `headers` to `undefined`.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode) Co-authored-by: justsisyphus <justsisyphus@users.noreply.github.com> Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>