Add Go Microsoft Entra foundation (#125)

* Add Go Microsoft Entra foundation

- Adds a native Microsoft OAuth/OIDC service with JWKS, RS256 ID tokens, token grants, Graph profile routes, logout, revoke, and JSON seed support.

- Wires Microsoft into the Go runtime, CLI seed loading, Vercel preview handler, scaffold defaults, docs, and agent skills.

- Covers authorization code, PKCE, refresh rotation, client credentials, v1 resource translation, runtime, CLI, and Vercel forwarding behavior in tests.

* Bind Microsoft refresh tokens to clients

* Format CLI index for CI