feat: implement authorization code flow for hca prod (ma-prod) (#4850)

[frano-m]

Summary

• Switches HCA prod (ma-prod) Google OAuth from implicit to authorization code flow.
• New client ID provisioned for the auth-code flow on the same Google Cloud project.
• Mirrors the ma-dev migration: replaces `GOOGLE_PROVIDER` const with a `getGoogleProvider(dataSourceUrl)` factory that derives the `authorize` endpoint from the Azul base URL (`https://service.azul.data.humancellatlas.org/user/authorize\`).
• Propagates `dataSourceUrl` through `getAuthentication` and `config.ts` (`makeConfig` now passes `DATA_URL` into `getAuthentication`).

Closes #4850

Test plan

• Sign in to prod HCA Data Browser and complete the Terra OAuth round-trip
• Sign out cleanly
• Refresh-token flow exercised end-to-end via Azul

🤖 Generated with Claude Code

[Copilot]

Pull request overview

Updates the HCA DCP ma-prod site configuration to use Google OAuth’s authorization code flow (instead of implicit), mirroring the existing ma-dev approach and deriving the Azul authorize endpoint from the configured DATA_URL.

Changes:

• Switch ma-prod Google OAuth configuration to OAUTH_FLOW.AUTHORIZATION_CODE with the newly provisioned prod client ID.
• Replace the ma-prod GOOGLE_PROVIDER constant with getGoogleProvider(dataSourceUrl) to derive authorize from the Azul base URL.
• Thread DATA_URL through config.ts → getAuthentication(dataSourceUrl) → getGoogleProvider(dataSourceUrl).

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
site-config/hca-dcp/ma-prod/config.ts	Passes DATA_URL into getAuthentication so auth endpoints can be derived from the Azul base URL.
site-config/hca-dcp/ma-prod/authentication/constants.ts	Introduces getGoogleProvider(dataSourceUrl) using auth-code flow and the new prod Google client ID; derives authorize from Azul.
site-config/hca-dcp/ma-prod/authentication/authentication.ts	Updates getAuthentication signature to accept dataSourceUrl and uses getGoogleProvider.

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