fix: 3D'解析失败'根因修复+错误信息可见

- watch immediate 首跑时 camera 未创建而 build() 触碰 camera
  → TypeError 被 catch 显示为'解析失败'
  移除 build 内相机定位(每帧 loop 已定位, 首跑安全)
- 移除 shadowMap.type 赋值(three r186 已移除 PCFSoft 常量)
- 解析失败时显示真实错误信息(console+画布标注)
- dist 重建, PCFSoft 赋值触发路径清零

frontend/src/components/WindoorThreed.vue

@@ -421,7 +421,6 @@ onMounted(() => {
   renderer = new THREE.WebGLRenderer({ canvas: cv, antialias: true, preserveDrawingBuffer: true })
   renderer.setSize(wrap.clientWidth, wrap.clientHeight)
   renderer.shadowMap.enabled = true
-  renderer.shadowMap.type = THREE.PCFSoftShadowMap
   camera = new THREE.PerspectiveCamera(50, wrap.clientWidth / wrap.clientHeight, 0.01, 100)
   cv.addEventListener('mousedown', onDown)
   window.addEventListener('mousemove', onMove)
@@ -430,7 +429,12 @@ onMounted(() => {
   cv.addEventListener('contextmenu', e => e.preventDefault())
   window.addEventListener('resize', onResize)
   watch(() => props.drawingData, () => {
-    try { if (props.drawingData) build(parseDrawing(props.drawingData)) } catch { info.value = '解析失败' }
+    try {
+      if (props.drawingData) build(parseDrawing(props.drawingData))
+    } catch (e) {
+      console.error('[WindoorThreed] 构建/解析失败:', e)
+      info.value = '解析失败: ' + (e as Error).message
+    }
   }, { immediate: true })
   watch([lightMode], () => applyLight())
   loop()