fix(mapping): correct region↔IO mapping per on-device measurement

Measured on real hardware: IO1=right IO2=left IO3=top IO4=middle IO5=bottom
(0x01=right 0x02=left 0x04=top 0x08=middle 0x10=bottom). The earlier verbal
'left=IO1/upper=IO2...' spec was wrong; this reverts to the original Phase-1
mapping, which the measurement confirms.

- protocol.js REGION constants + getRegionName + REGION_NAMES
- CRITICAL: buildVendorCommand ioMasks was built from REGION.* constants whose
  values just flipped, scrambling IO slot order; pin to literal [0x01..0x10]
- diagnosis.js REGION_DEFS key↔mask; pd_region_map values unchanged (PD is
  keyed by orientation, which is stable) — right=PD5 left=PD1 top=PD2
  middle=PD3,6,7 bottom=PD4
- common.js region labels back to right/left/top/middle/bottom (上/中/下)
- treatment-setup / manual-treatment / treating / scan-report / ble-debug
  face-map bindings and REGION_MAP realigned
- verified: mock pipeline lands left→IO2, middle→IO4 correctly

miniprogram/pages/ble-debug/ble-debug.wxml

@@ -37,11 +37,11 @@
     <view class="card">
       <view class="card-title">点分区 → 该区 2 秒治疗（对物理位置）</view>
       <view class="face-map">
-        <view class="face-region forehead" bindtap="onTapRegion" data-mask="2">中上\nIO2</view>
-        <view class="face-region left-cheek" bindtap="onTapRegion" data-mask="1">左\nIO1</view>
-        <view class="face-region right-cheek" bindtap="onTapRegion" data-mask="16">右\nIO5</view>
-        <view class="face-region nose" bindtap="onTapRegion" data-mask="4">中\nIO3</view>
-        <view class="face-region chin" bindtap="onTapRegion" data-mask="8">中下\nIO4</view>
+        <view class="face-region forehead" bindtap="onTapRegion" data-mask="4">上\nIO3</view>
+        <view class="face-region left-cheek" bindtap="onTapRegion" data-mask="2">左\nIO2</view>
+        <view class="face-region right-cheek" bindtap="onTapRegion" data-mask="1">右\nIO1</view>
+        <view class="face-region nose" bindtap="onTapRegion" data-mask="8">中\nIO4</view>
+        <view class="face-region chin" bindtap="onTapRegion" data-mask="16">下\nIO5</view>
       </view>
     </view>