Make digital clock format configurable via CONFIG.timeFormat

config.js

@@ -1,14 +1,19 @@
 /* Application configuration
- * debug      - Show debug panel (0/1)
- * theme      - Color palette: 'ash', 'gruvbox' or 'nord'
- * units      - Measurement units: 'metric' or 'imperial'
- * language   - UI language: 'de' or 'en'
+ * debug       - Show debug panel (0/1)
+ * theme       - Color palette: 'ash', 'gruvbox' or 'nord'
+ * units       - Measurement units: 'metric' or 'imperial'
+ * language    - UI language: 'de' or 'en'
+ * timeFormat  - ISO-8601-ish format string for the digital clock.
+ *               Date-only: YYYY, YYYY-MM, YYYY-MM-DD
+ *               Date-time: above + T + HH:mm, HH:mm:ss, HH:mm:ss.sss
+ *               Optional timezone offset (e.g. +02:00)
  */
 window.CONFIG = {
     debug: 1,
     theme: 'ash',
     units: 'metric',
-    language: 'en'
+    language: 'en',
+    timeFormat: 'HH:mm:ss'
 };
 
 // List of available themes. The key is the theme id (used in config.theme),