Time left and finished go by the length the player measured

A feed can be minutes out: ReThinking's gave 41:23 for a 43:48 file,
which read 0:08 left with 2:33 to play. The player's length is kept in
entry_state beside the position, per listener, where no scan can put
the feed's figure back, and preferred to the feed's.

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

CHANGELOG.md

@@ -12,6 +12,8 @@ The long form, with what was wrong before and how it was found, is in
 
 ### Fixed
 
+- Time left, and when an episode counts as finished, go by the length your player measured
+  rather than the feed's, which can be minutes out: one episode said 0:08 left with 2:33 to play.
 - 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.