FIX: State-based display refresh logic
- Problem: Screen would occasionally fail to update if the ESP32 was busy
(fetching data or reconnecting WiFi) during the exact 00/15/30/45 minute mark.
- Fix: Switched from "Event-Based" (refresh only AT minute X) to "State-Based"
(refresh IF current time != last refresh time). This ensures the screen
updates immediately even if the device was busy during the transition.
- Updated version strings throughout the UI.
