Fix ui theme default when no setting saved, fixes #210

Author: brunchboy

CHANGELOG.md

@@ -10,6 +10,7 @@ This change log follows the conventions of
 
 - Changed the build workflow in GitHub Actions to go back to using Java 17 because of a [bug in the Clojure compiler](https://clojure.atlassian.net/browse/CLJ-2838) that would cause BLT to crash when running on any Java version older than Java 21 if it was compiled under Java 21.
   Once that compiler bug is fixed, we can go back to compiling under Java 21.
+- Brand new BLT installs, or upgrades from versions prior to 8 are supposed to start in a dark UI theme, but are actually showing the light theme (even though the Settings window says dark).
 
 
 ## [8.0.0] - 2025-07-21

src/beat_link_trigger/prefs.clj

@@ -237,9 +237,10 @@
    (dark-mode? (get-preferences)))
   ([preferences]
    (case (:ui-mode preferences)
-     :light false
-     :dark  true
-     (.isDark theme-detector))))  ; Using system setting.
+     :light  false
+     :dark   true
+     :system (.isDark theme-detector)
+     true)))  ; Default to dark if the user never set anything.
 
 
 (defn gear-icon