Lists repositories the workspace’s connected SCM source can see, for the create-flow repo picker. Given a provider (github, gitlab, bitbucket, or the dev-only mockhub) and an optional q, runs a provider-side name search when q is present (so a huge org need not be enumerated to find a repo) or lists the first page of the account otherwise, returning the bare repo name (the scan filter key), the owner/repo fullName, and whether the repo is archived. Results are capped; hasMore signals the caller to narrow with q. 404s when the provider is not connected for the workspace or the onboarding feature flag is off.