Add ollama_api_key support for remote Ollama endpoints

[geeksilva97]

What this does

Allow callinc remote Ollama endpoints for using ollama cloud models

Type of change

• Bug fix
• New feature
• Breaking change
• Documentation
• Performance improvement

Scope check

• I read the Contributing Guide
• This aligns with RubyLLM's focus on LLM communication
• This isn't application-specific logic that belongs in user code
• This benefits most users, not just my specific use case

Required for new features

• I opened an issue before writing code and received maintainer approval
• Linked issue: #___

PRs for new features or enhancements without a prior approved issue will be closed.

Quality check

• I ran overcommit --install and all hooks pass
• I tested my changes thoroughly
  • For provider changes: Re-recorded VCR cassettes with bundle exec rake vcr:record[provider_name]
  • All tests pass: bundle exec rspec
• I updated documentation if needed
• I didn't modify auto-generated files manually (models.json, aliases.json)

AI-generated code

• [ x ] I used AI tools to help write this code
• [ x ] I have reviewed and understand all generated code (required if above is checked)

[crmne]

.

Superseded due to shell-escaped formatting corruption in review body.

[crmne]

Thanks for the contribution. I’m requesting changes because the repository contribution requirements for new features are not met yet:

1. New features require a prior approved issue, and this PR has no linked issue (closingIssuesReferences is empty and the PR checklist leaves that unchecked).
2. The quality checklist indicates overcommit hooks were not run. Please run the configured hooks and update the checklist.
3. This introduces ollama_api_key support, but there is no accompanying docs update (for example, in docs/_getting_started/configuration.md), and the PR checklist leaves documentation unchecked.

Please address these process requirements and re-request review.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 80.14%. Comparing base (bed3bfb) to head (f91335f).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #612   +/-   ##
=======================================
  Coverage   80.13%   80.14%           
=======================================
  Files         113      113           
  Lines        5095     5096    +1     
  Branches     1307     1308    +1     
=======================================
+ Hits         4083     4084    +1     
  Misses       1012     1012           

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[geeksilva97]

Thanks for the contribution. I’m requesting changes because the repository contribution requirements for new features are not met yet:

1. New features require a prior approved issue, and this PR has no linked issue (closingIssuesReferences is empty and the PR checklist leaves that unchecked).
2. The quality checklist indicates overcommit hooks were not run. Please run the configured hooks and update the checklist.
3. This introduces ollama_api_key support, but there is no accompanying docs update (for example, in docs/_getting_started/configuration.md), and the PR checklist leaves documentation unchecked.

Please address these process requirements and re-request review.

Will do. Thanks