feat: app rate limit (#5844)

Co-authored-by: liuzhenghua-jk <liuzhenghua-jk@360shuke.com>
Co-authored-by: takatost <takatost@gmail.com>

api/configs/feature/__init__.py

@@ -31,6 +31,10 @@ class AppExecutionConfig(BaseSettings):
         description='execution timeout in seconds for app execution',
         default=1200,
     )
+    APP_MAX_ACTIVE_REQUESTS: NonNegativeInt = Field(
+        description='max active request per app, 0 means unlimited',
+        default=0,
+    )
 
 
 class CodeExecutionSandboxConfig(BaseSettings):