resolveRoleForRequest and resolveShareRole duplicated the security invariant
'role exists, not soft-deleted, enabled, workspace-scoped, else null'. Move it to
AiAgentRoleRepo.findLiveEnabled(id, workspaceId) (deletedAt IS NULL + enabled +
workspace scope) and have both services call it, preserving each one's roleId
derivation + null handling. (describeProviderError half of #95 was done earlier.)
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
3953ecdb17