docs(todo): magazine podcasts via Open Notebook's multi-speaker generator

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

TODO.md

@@ -64,6 +64,17 @@ not part of this order.
 
 ### P1 — next, highest user impact
 
+- [ ] **M — Magazine podcasts via Open Notebook (multi-speaker).** [Open Notebook](https://github.com/lfnovo/open-notebook)
+  has an advanced multi-speaker podcast generator ("Generate professional podcasts") that could make
+  the magazine podcast mode much better. It already runs on the LAN at `192.168.178.19` (Docker: API
+  `:5055`, UI `:8500`, SurrealDB `:8501`). Two options, decide after reading its API and licence:
+  (a) **hook it up** — send an approved article to Open Notebook as a source, ask it for a podcast
+  script/episode, and play or voice the result here (a new external integration: check licence, data
+  flow — article text leaves this app —, auth, rate/cost, and availability; keep it optional with the
+  current podcast mode as fallback); or (b) **copy the approach** — port its speaker/episode-profile
+  design into the existing podcast mode and voice it with this app's own TTS voices. Prefer (a) if its
+  API exposes script generation cleanly, since the voices would still come from here.
+
 - [ ] **M — Magazine: let the reader decide the region order.** On the boundary-review page,
   give each region an explicit reading position: click the regions in the order they should be
   read, or type a number into each one. The order drives playback and the OCR-results list.