make dev/dev-debug 구분.

userfront/lib/core/services/log_policy.dart

@@ -29,23 +29,37 @@ class LogPolicy {
         env == 'staging';
   }
 
-  static bool parseBoolFlag(String? raw) {
+  static ({bool enabled, bool specified}) parseOptionalBoolFlag(String? raw) {
     final value = (raw ?? '').trim().toLowerCase();
-    return value == '1' ||
+    if (value == '1' ||
         value == 'true' ||
         value == 'yes' ||
         value == 'y' ||
-        value == 'on';
+        value == 'on') {
+      return (enabled: true, specified: true);
+    }
+    if (value == '0' ||
+        value == 'false' ||
+        value == 'no' ||
+        value == 'n' ||
+        value == 'off') {
+      return (enabled: false, specified: true);
+    }
+    return (enabled: false, specified: false);
   }
 
   static bool debugEnabled({
     required String? appEnv,
     required String? productionDebugFlag,
   }) {
+    final flag = parseOptionalBoolFlag(productionDebugFlag);
+    if (flag.specified) {
+      return flag.enabled;
+    }
     if (!isProductionEnv(appEnv)) {
       return true;
     }
-    return parseBoolFlag(productionDebugFlag);
+    return false;
   }
 
   static bool shouldRelayClientLog({