feat(face): 人脸库为空时自动进入新用户采集模式

- 新增 newUserCollect() 方法，人脸数据库记录为零时自动显示采集界面
- onResume 中异步查询人脸数量，据此决定进入采集模式或正常识别模式
- 修复 isFirstOpen 依赖 1000ms 延迟的竞态问题，改为立即置 false
- 顺带修改 FunActivity 按钮文案为「清除并拉取全量数据」

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/src/main/java/com/sw/platecabinet/activity/LoginByFaceActivity.kt

@@ -59,6 +59,7 @@ import com.sw.platecabinet.utils.SoundPoolUtil
 import com.sw.platecabinet.utils.SpTool
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
 import org.greenrobot.eventbus.EventBus
 import org.greenrobot.eventbus.Subscribe
 import org.greenrobot.eventbus.ThreadMode
@@ -348,6 +349,20 @@ class LoginByFaceActivity : BaseActivity<ActivityLoginFaceBinding>(),
         binding.ivCollectPhoto.visible()
     }
 
+    private fun newUserCollect() {
+        recognizeCountDownUtil.cancelCountDown()
+        binding.tvToInit.text = ""
+        binding.tvSimilarValue.text = ""
+        binding.llCollectButton.visible()
+        binding.btnRetry.gone()
+        binding.btnCollect.run {
+            visible()
+            text = "新用户采集"
+        }
+        binding.ivCollectPhoto.gone()
+        resumeCamera()
+    }
+
     /**
      * 查询餐盘数据
      */
@@ -674,13 +689,24 @@ class LoginByFaceActivity : BaseActivity<ActivityLoginFaceBinding>(),
         super.onResume()
         try {
             if (isFirstOpen) {
+                isFirstOpen = false
                 goInitActivity()
-                binding.root.postDelayed({
-                    isFirstOpen = false
-                }, 1000)
                 return
             }
-            resetRecognizeState()
+
+            lifecycleScope.launch {
+                try {
+                    val faceDao = FaceDatabase.getInstance(this@LoginByFaceActivity).faceDao()
+                    val faceCount = withContext(Dispatchers.IO) { faceDao.faceCount }
+                    if (faceCount == 0) {
+                        newUserCollect()
+                    } else {
+                        resetRecognizeState()
+                    }
+                } catch (e: Exception) {
+                    e.printStackTrace()
+                }
+            }
         } catch (e: Exception) {
             e.printStackTrace()
         }

app/src/main/res/layout/activity_fun.xml

@@ -65,7 +65,7 @@
         android:layout_marginHorizontal="50dp"
         android:paddingHorizontal="30dp"
         android:background="@drawable/btn_outline"
-        android:text="清除并重新拉取数据"
+        android:text="清除并拉取全量数据"
         android:textColor="#FFCC99" />
 
     <TextView