fix(dashboard): restore external OAuth management

[disintegrator]

Summary

• restore the external OAuth setup action on the rewritten toolset authentication surface
• open the existing OAuth wizard directly on the external OAuth form
• preserve the existing eligibility rules for enabled public MCP servers
• cover the eligibility matrix, setup-action plumbing, and direct wizard entry with tests
• add a patch changeset for the dashboard package

Testing

• pnpm -F dashboard test toolsetAuthSurface OAuthWizard AuthenticationSection (32 tests passed)
• pnpm -F dashboard type-check
• pnpm -F dashboard lint
• pnpm exec changeset status --since=main
• manually verified the eligible toolset flow: action appears, opens the external OAuth form directly, validates placeholder metadata, and enables submission without submitting

Demo

Linear: AIS-364

Linear Issue: AIS-364

  

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Summary by cubic

Restores external OAuth management on the MCP toolset Authentication screen. Adds a “Configure External OAuth” action that opens the OAuth wizard directly on the external form. Aligns with Linear AIS-364.

• Bug Fixes

  • Show “Configure External OAuth” only for eligible servers: mcpEnabled + mcpIsPublic and either an OAuth2 auth code flow or an attached external MCP source requiring OAuth.
  • Wizard accepts initialPath="external" and jumps to the external form; pre-fills when discovered metadata is v2.1.
  • Adds an additionalSetupAction path so the button appears before a session issuer exists.
  • Keeps legacy eligibility rules to avoid exposing unusable config on the serve path.
  • Adds tests for the new entry point and gating (OAuthWizard, toolsetAuthSurface, AuthenticationSection).

• Dependencies

  • Adds a dashboard changeset to release this as a patch.

^{Written for commit ef81a9d. Summary will update on new commits.}

[linear-code]

AIS-364

[changeset-bot]

🦋 Changeset detected

Latest commit: ef81a9d

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
dashboard	Patch

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[cubic-dev-ai]

No issues found across 10 files

_{Re-trigger cubic}