fix(ui): one watch-progress colour in app chrome and in the player (#1798)

.changes/ui-watch-progress-colour.md

@@ -0,0 +1,9 @@
+---
+type: fix
+area: ui
+---
+
+Watch progress has one colour again: your theme's accent on dashboard cards
+and catalog posters, and the player's blue everywhere inside the player, so
+the next episode's bar no longer turns red in the Up Next rail and the
+fullscreen episode list.