refactor: move TileLayoutHelper from DisplayManager.h to Style.h

- Pure static helper class moved from DisplayManager.h to Style.h
- Drivers now use TileLayoutHelper::calculateLayouts() directly
- Remove extern DisplayManager references from display drivers
- Drop LGFX_USE_V1 build flag (no longer needed)
- Add delay(LOOP_YIELD_MS) in S3 loop to prevent watchdog

boards/esp32-s3-lcd-43/DisplayDriverGFX.cpp

@@ -6,10 +6,10 @@
 
 #include <Arduino.h>
 #include <KlubhausCore.h>
+#include <Style.h>
 
 // ── Globals ──
 static LGFX* _gfx = nullptr;
-extern DisplayManager display;
 
 // ── Forward declarations ──
 static void initDisplay();
@@ -443,10 +443,11 @@ void DisplayDriverGFX::drawDashboard(const ScreenState& state) {
         },
         safeWifi.w);
 
-    // Get tile layouts from library helper
-    int tileCount = display.calculateDashboardLayouts(STYLE_HEADER_HEIGHT, STYLE_TILE_GAP);
-    display.setHeaderHeight(STYLE_HEADER_HEIGHT);
-    const TileLayout* layouts = display.getTileLayouts();
+    // Calculate tile layouts using TileLayoutHelper
+    TileLayout layouts[DASHBOARD_TILE_COUNT];
+    int gridCols, gridRows;
+    int tileCount = TileLayoutHelper::calculateLayouts(
+        DISP_W, DISP_H, STYLE_HEADER_HEIGHT, STYLE_TILE_GAP, layouts, &gridCols, &gridRows);
 
     const char* tileLabels[] = { "Alert", "Silent", "Status", "Reboot" };
     const uint16_t tileColors[] = { 0x0280, 0x0400, 0x0440, 0x0100 };