[App] Add cloud platform exception (#13928)

Co-authored-by: Adrian Wälchli <aedu.waelchli@gmail.com>

src/lightning_app/core/work.py

@@ -518,7 +518,11 @@ class LightningWork(abc.ABC):
 
     @abc.abstractmethod
     def run(self, *args, **kwargs):
-        """Override to add your own logic."""
+        """Override to add your own logic.
+
+        Raises:
+            LightningPlatformException: If resource exceeds platform quotas or other constraints.
+        """
         pass
 
     def on_exception(self, exception: BaseException):

src/lightning_app/utilities/exceptions.py

@@ -41,6 +41,14 @@ class LightningWorkException(Exception):
     """Exception used to inform users of misuse with LightningWork."""
 
 
+class LightningPlatformException(Exception):  # pragma: no cover
+    """Exception used to inform users of issues related to platform the LightningApp is running on.
+
+    It gets raised by the Lightning Launcher on the platform side when the app is running in the cloud, and is useful
+    when framework or user code needs to catch exceptions specific to the platform, e.g., when resources exceed quotas.
+    """
+
+
 class LightningAppStateException(Exception):
     """Exception to inform users of app state errors."""