The separate error strings for each cloud credential provider (Bedrock, Vertex, Foundry, Mantle, Anthropic-on-AWS) have been consolidated into a single generic credential error factory.
Details
All credential providers now use: "[Provider] credentials are managed by the desktop app, but none are available. The app may have quit or its credential file is stale — restart the desktop app."
A new explicit message for incompatible credential types: "Background agents and teammates are not supported for this credential kind. Run this from the main session, or switch the desktop app to a profile-based or API-key credential. If this is the main session, restart the desktop app."
Credential error factory (search for "host-managed provider credentials unavailable" and "Background agents and teammates are not supported for this credential kind")
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
