List sources

Returns a bare array by default; pass ?envelope=true for the paginated {items, pagination} shape. Filter by ?orgId=, ?orgSlug=, ?slug= (exact source slug — one row per org that has a source with this slug, for detecting an ambiguous bare slug across orgs; distinct from the ?q= substring search), ?productSlug=, ?type=, ?has_feed=, ?stale=, ?category=, ?kind=, ?independent=true, ?hasChangelog=false (sources with no tracked CHANGELOG file), ?minRels30d=N (sources with at least N visible releases in the last 30 days). Free-text search via ?q=.