Inbound payload for <code>POST /workspaces/{workspaceSlug</code>/connections}.

<p><code>userInput</code> is intentionally a free-form map so per-kind ConnectionStrategy implementations can dictate their own field schema (e.g. Outline needs <code>server_url</code>; GitHub needs nothing because the install URL is server-configured).

Flat response for <code>POST /workspaces/{workspaceSlug</code>/connections}.

<p>Two outcomes, distinguished by <code>type</code>: <ul> <li><code>REDIRECT</code> — OAuth / App-install flows (GitHub, Slack). <code>vendorUrl</code> is the URL to bounce the browser to; the signed OAuth state is already embedded in it.</li> <li><code>LINKED</code> — inline-credential flows (GitLab PAT). <code>connectionId</code> is the newly-created Connection; no further round-trip is needed.</li> </ul> <p>Deliberately a flat record (nullable per-variant fields) rather than a sealed <code>oneOf</code> hierarchy: a discriminated union serialises to OpenAPI <code>oneOf + discriminator</code>, which the webapp's hey-api react-query transformer mishandles. A flat shape round-trips cleanly through code generation, so the webapp consumes the generated client instead of a hand-rolled fetch wrapper.