implement dashboard on wake

sketches/doorbell-touch-esp32-32e/Dashboard.h

@@ -1,5 +1,6 @@
 #pragma once
 #include <TFT_eSPI.h>
+#include "ScreenData.h"
 
 // Grid layout constants
 #define DASH_COLS      3
@@ -8,8 +9,8 @@
 #define DASH_TOP_BAR   40
 
 // Tile dimensions (calculated for 480x320)
-#define TILE_W         ((480 - (DASH_COLS + 1) * DASH_MARGIN) / DASH_COLS)  // ~148
-#define TILE_H         ((320 - DASH_TOP_BAR - (DASH_ROWS + 1) * DASH_MARGIN) / DASH_ROWS)  // ~128
+#define TILE_W  ((480 - (DASH_COLS + 1) * DASH_MARGIN) / DASH_COLS)   // ~148
+#define TILE_H  ((320 - DASH_TOP_BAR - (DASH_ROWS + 1) * DASH_MARGIN) / DASH_ROWS)  // ~128
 
 // Tile IDs
 enum TileID : uint8_t {
@@ -23,30 +24,38 @@ enum TileID : uint8_t {
 };
 
 struct TileData {
-  const char* icon;       // emoji/symbol character
-  const char* label;      // tile name
-  char        value[32];  // dynamic value text
-  char        sub[32];    // secondary line
+  const char* icon;
+  const char* label;
+  char        value[32];
+  char        sub[32];
   uint16_t    bgColor;
   uint16_t    fgColor;
-  bool        dirty;      // needs redraw
+  bool        dirty;
 };
 
 class Dashboard {
 public:
   Dashboard(TFT_eSPI& tft);
 
-  void begin();
-  void drawAll();
+  void begin();                       // create sprite (call once)
+  void drawAll();                     // fill screen + draw all tiles
   void drawTopBar(const char* time, int rssi, bool wifiOk);
   void updateTile(TileID id, const char* value, const char* sub = nullptr);
-  int  handleTouch(int x, int y);  // returns TileID or -1
+  int  handleTouch(int x, int y);     // returns TileID or -1
+
+  // Populate tiles from ScreenState — only redraws changed tiles
+  void refreshFromState(const ScreenState& state);
 
 private:
   TFT_eSPI&    _tft;
   TFT_eSprite  _sprite;
   TileData     _tiles[TILE_COUNT];
 
+  // Cached top bar values for dirty check
+  char     _barTime[12]  = "";
+  int      _barRSSI      = 0;
+  bool     _barWifiOk    = false;
+
   void drawTile(TileID id);
   void tilePosition(TileID id, int& x, int& y);
 };