refactor(boards): Move Puchi BLE to ZMK variant by default

Make the standard Puchi BLE board ID be `puchi_ble/nrf52840/zmk` or
`puchi_ble//zmk` by shorthand.

app/boards/keycapsss/puchi_ble/Kconfig.defconfig

@@ -3,9 +3,6 @@
 
 if BOARD_PUCHI_BLE
 
-config BOARD
-    default "puchi_ble"
-
 if USB_DEVICE_STACK
 
 config USB_NRFX
@@ -13,7 +10,4 @@ config USB_NRFX
 
 endif # USB_DEVICE_STACK
 
-config BT_CTLR
-    default BT
-
 endif # BOARD_PUCHI_BLE

app/boards/keycapsss/puchi_ble/Kconfig.puchi_ble

@@ -5,6 +5,6 @@
 
 config BOARD_PUCHI_BLE
     select SOC_NRF52840_QIAA
-    imply RETAINED_MEM
-    imply RETENTION
-    imply RETENTION_BOOT_MODE
+    imply RETAINED_MEM if BOARD_PUCHI_BLE_NRF52840_ZMK
+    imply RETENTION if BOARD_PUCHI_BLE_NRF52840_ZMK
+    imply RETENTION_BOOT_MODE if BOARD_PUCHI_BLE_NRF52840_ZMK

app/boards/keycapsss/puchi_ble/board.yml

@@ -1,5 +1,5 @@
 board:
-  name: puchi_ble
-  vendor: keycapsss
-  socs:
-    - name: nrf52840
+  extend: puchi_ble
+  variants:
+    - name: zmk
+      qualifier: nrf52840

app/boards/keycapsss/puchi_ble/puchi_ble.zmk.yml

@@ -1,5 +1,5 @@
 file_format: "1"
-id: puchi_ble
+id: puchi_ble//zmk
 name: Puchi-BLE V1
 type: board
 arch: arm

app/boards/keycapsss/puchi_ble/puchi_ble_nrf52840_zmk.dts

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2026 The ZMK Contributors
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#include <../boards/keycapsss/puchi_ble/puchi_ble.dts>
+#include <common/nordic/nrf52840_uf2_boot_mode.dtsi>
+
+
+/ {
+    chosen {
+        zmk,battery = &vbatt;
+    };
+
+    // Node name must match original "EXT_POWER" label to preserve user settings.
+    EXT_POWER {
+        compatible = "zmk,ext-power-generic";
+        control-gpios = <&gpio1 9 GPIO_ACTIVE_LOW>;
+    };
+
+    vbatt: vbatt {
+        compatible = "zmk,battery-voltage-divider";
+        io-channels = <&adc 2>;
+        output-ohms = <2000000>;
+        full-ohms = <(2000000 + 820000)>;
+    };
+};
+

app/module/boards/keycapsss/puchi_ble/Kconfig.defconfig

@@ -0,0 +1,16 @@
+# Copyright (c) 2026 The ZMK Contributors
+# SPDX-License-Identifier: MIT
+
+if BOARD_PUCHI_BLE
+
+config BOARD
+    default "puchi_ble"
+
+if USB_DEVICE_STACK
+
+config USB_NRFX
+    default y
+
+endif # USB_DEVICE_STACK
+
+endif # BOARD_PUCHI_BLE

app/module/boards/keycapsss/puchi_ble/Kconfig.puchi_ble

@@ -0,0 +1,10 @@
+# Puchi-BLE board configuration
+
+# Copyright (c) 2026 The ZMK Contributors
+# SPDX-License-Identifier: MIT
+
+config BOARD_PUCHI_BLE
+    select SOC_NRF52840_QIAA
+    imply RETAINED_MEM
+    imply RETENTION
+    imply RETENTION_BOOT_MODE

app/module/boards/keycapsss/puchi_ble/board.yml

@@ -0,0 +1,5 @@
+board:
+  name: puchi_ble
+  vendor: keycapsss
+  socs:
+    - name: nrf52840

app/module/boards/keycapsss/puchi_ble/pre_dt_board.cmake

@@ -0,0 +1,9 @@
+#
+# Copyright (c) 2026 The ZMK Contributors
+# SPDX-License-Identifier: MIT
+#
+
+# Suppresses duplicate unit-address warning at build time for power, clock, acl and flash-controller
+# https://docs.zephyrproject.org/latest/build/dts/intro-input-output.html
+
+list(APPEND EXTRA_DTC_FLAGS "-Wno-unique_unit_address_if_enabled")

app/module/boards/keycapsss/puchi_ble/puchi_ble.zmk.yml

@@ -0,0 +1,10 @@
+file_format: "1"
+id: puchi_ble
+name: Puchi-BLE V1
+type: board
+arch: arm
+outputs:
+  - usb
+  - ble
+url: https://keycapsss.com/keyboard-parts/mcu-controller/202/puchi-ble-wireless-microcontroller
+exposes: [pro_micro]

app/module/boards/keycapsss/puchi_ble/puchi_ble_defconfig

@@ -0,0 +1,15 @@
+# Copyright (c) 2026 The ZMK Contributors
+# SPDX-License-Identifier: MIT
+
+# Enable MPU
+CONFIG_ARM_MPU=y
+
+# enable GPIO
+CONFIG_GPIO=y
+
+# Use pinctrl
+CONFIG_PINCTRL=y
+
+CONFIG_USE_DT_CODE_PARTITION=y
+CONFIG_BUILD_OUTPUT_UF2=y
+