BitAds

Reviewed overlay for SN16 BitAds. The former bitads.ai website/docs domain no longer resolves (DNS lame delegation — the domain's own nameservers refuse the query, re-confirmed this pass), so website_url/docs_url are nulled until a live domain is confirmed. The operator's active code has moved from FirstTensorLabs/BitAds (still 404) to study-service/BitAds.ai (live) -- the source-repo surface was still pointing at the dead URL with probing disabled despite the top-level source_repo field already being correct; fixed to point at the live repo with probing re-enabled. Two more community-submitted surfaces (min-compute, TaoMarketCap snapshot) had no probe config at all (the registry-wide gap tracked in #5932), fixed. Common API/OpenAPI/Swagger paths previously returned website HTML instead of machine-readable API/schema responses, so they are excluded as content mismatches.