Keep the run_shell timeout changelog note under Unreleased

0.2.104 is already tagged. Folding this into that section would
claim a released cut contains work that is not in it.

Author: TheGreatAxios

CHANGELOG.md

@@ -11,7 +11,7 @@ matching `## [X.Y.Z]` section (plus install instructions). Do not maintain
 parallel copies under `docs/` or `scripts/notes/`. At cut time: rename
 `## [Unreleased]` to `## [X.Y.Z] - YYYY-MM-DD`, then run the release script.
 
-## [0.2.104] - 2026-08-23
+## [Unreleased]
 
 ### Plugins
 
@@ -21,6 +21,7 @@ parallel copies under `docs/` or `scripts/notes/`. At cut time: rename
   timeout and does not invent one on its own. Abort and the output-byte cap are
   unchanged.
 
+## [0.2.104] - 2026-08-23
 ### TUI
 
 - **Taller live chain-of-thought preview.** Parent reasoning still paints