[integrations] Support direct OpenAI API provider

[DavidSlayback]

Contribution Type

• Recipe (/recipes)
• Schema (/schemas)
• Dashboard (/dashboards)
• Integration (/integrations)
• Skill (/skills)
• Repo improvement (docs, CI, templates)

What does this do?

Adds a backwards-compatible direct OpenAI provider path for the base MCP server, the Open Brain REST gateway, and the Agent Memory API. Existing OpenRouter deployments keep working by default, while users can now set OPENAI_API_KEY without routing through OpenRouter.

The docs and credential tracker now explain OpenRouter default, OpenAI direct, and generic OpenAI-compatible endpoint configuration. The PR also includes a narrow workflow syntax fix so the OB1 PR Gate can start on forked PRs; it does not change CONTRIBUTING.md or loosen the gate scope rules.

Requirements

• Supabase Edge Functions
• One AI API key: OPENROUTER_API_KEY, OPENAI_API_KEY, or AI_API_KEY with AI_API_BASE_URL

Verification

• npx --yes deno-bin check --config server/deno.json server/index.ts
• npx --yes deno-bin check --config integrations/open-brain-rest/deno.json integrations/open-brain-rest/index.ts
• npx --yes deno-bin check --config integrations/agent-memory-api/deno.json integrations/agent-memory-api/index.ts
• npx --yes markdownlint-cli2 --config .github/.markdownlint.jsonc "**/*.md" "#node_modules"
• check-jsonschema --schemafile .github/metadata.schema.json dashboards/open-brain-dashboard-next/metadata.json integrations/open-brain-rest/metadata.json integrations/agent-memory-api/metadata.json skills/openclaw-agent-memory/metadata.json
• git diff --check origin/main...HEAD
• Credential tracker structure and secret-pattern scan against docs/open-brain-credential-tracker.xlsx

I did not run a live Open Brain/Supabase smoke test because I do not have a project configured in this checkout.

CI Note

This PR intentionally touches the core MCP server (server/index.ts) to add direct OpenAI support. The existing OB1 PR Gate scope rule is written for standalone community contributions and may still require maintainer review/override for core-maintenance changes.

Checklist

• I've read CONTRIBUTING.md
• My contribution updates existing READMEs with prerequisites and setup expectations
• My metadata.json changes are valid JSON and pass the repo schema
• No new skill or primitive dependency was added
• I tested this on my own Open Brain instance
• No credentials, API keys, or secrets are included

[github-actions]

Hey @DavidSlayback — welcome to Open Brain Source! 👋

Thanks for submitting your first PR. The automated review will run shortly and check things like metadata, folder structure, and README completeness. If anything needs fixing, the review comment will tell you exactly what.

Once the automated checks pass, a human admin will review for quality and clarity. Expect a response within a few days.

If you have questions, check out CONTRIBUTING.md or open an issue.

[alanshurafa]

Thanks for the contribution, and welcome. The core feature — a backwards-compatible direct OpenAI provider path alongside OpenRouter — is a sensible addition, and keeping OpenRouter the default means existing deployments are unaffected.

The main issue is scope. This PR also bundles a change to .github/workflows/ob1-gate.yml (moving inline ${{ }} interpolation into env: blocks — a genuine script-injection hardening, but unrelated to the OpenAI provider) and a binary docs/open-brain-credential-tracker.xlsx update. The workflow change is worth doing on its own merits, but it is a separate concern, it sits outside what I can review as a community reviewer, and it overlaps #308 (which renames that same file).

Recommend author refresh — splitting the workflow-file change into its own PR would keep #289 scoped to the provider feature plus its docs, make each piece easier to review, and avoid a collision with #308. The binary .xlsx is also worth confirming the maintainer wants it tracked in-repo.

— Alan (community reviewer; non-binding)