Save a position only from a player that has played since its last save

A tab left paused further into an episode saved its older place as it
reloaded, over where the listener had got to since, and the episode
dropped out of Currently Listening. A jump back is now saved at once.

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

CHANGELOG.md

@@ -10,6 +10,11 @@ The long form, with what was wrong before and how it was found, is in
 
 ## [Unreleased]
 
+### Fixed
+
+- A player left open in another tab or on another device no longer saves its older place over
+  where you have got to since, which could drop an episode out of Currently Listening.
+
 ## [0.6.0] - 2026-09-15
 
 ### Added