HANDOFF: next step is TASK 4 ship step 3 — encoder + RTMP push

HANDOFF.md

@@ -63,9 +63,10 @@
   - Round-3 redirect fallback fires only when identity-domain nodeinfo fails;
     the root follow happens automatically (HttpClient default auto-redirect),
     and `RequestMessage.RequestUri.Host` is read from the final response.
-- **Next step:** commit + push the docs backfill (ai.md / README.md / TASKS.md
-  schema section / THIRD-PARTY-NOTICES.txt) once the user confirms. Nothing
-  else queued — do not expand the task queue on your own.
+- **Next step:** TASK 4 ship step 3 — the encoder + RTMP push (FFmpeg subprocess:
+  frames via stdin, stderr health parsing, FLV mux + push to the cached reusable
+  stream's ingestion URL). Nothing else queued — do not expand the task queue on
+  your own.
 
 - **Secret/DB/port facts live:** OAuth client id/secret in `Helpers/OAuthCredentials.cs`;
   OAuth session token in `Helpers/TokenStore.cs` (DPAPI → `%APPDATA%\ytLlive\ytLlive.auth`);