Add project handoff and Pico MVP documentation

docs/wiring.md

@@ -592,3 +592,46 @@ Only three wires need to return to the ESP32:
     3.3V
     GPIO4
     GND
+
+---
+
+## Pico Dashboard Wiring
+
+The Pico dashboard should be powered from a local 12V-to-5V buck converter in the dash enclosure.
+
+Rear enclosure sends fused 12V over CAT5e.
+
+Dash side:
+
+    CAT5e +12V -> buck IN+
+    CAT5e GND  -> buck IN-
+
+    buck OUT+ 5V -> Pico VSYS
+    buck OUT+ 5V -> Display VCC
+
+    buck OUT- GND -> Pico GND
+    buck OUT- GND -> Display GND
+
+Display wiring:
+
+    SCLK     -> Pico GPIO18
+    MOSI     -> Pico GPIO19
+    LCD_CS   -> Pico GPIO17
+    LCD_DC   -> Pico GPIO16
+    LCD_RST  -> Pico GPIO20
+    LCD_BL   -> Pico GPIO21
+
+Touch wiring, reserved for future:
+
+    TP_SDA   -> Pico GPIO26
+    TP_SCL   -> Pico GPIO27
+    TP_INT   -> Pico GPIO28
+    TP_RST   -> Pico GPIO15
+
+UART wiring:
+
+    ESP32 GPIO21 TX -> Pico GPIO0 RX
+    ESP32 GPIO22 RX -> Pico GPIO1 TX
+    ESP32 GND       -> Pico GND
+
+Do not use the ESP32 6-pin UART header for the dashboard UART. It appears to be connected to RXD/TXD for UART0/programming/debug.