Add exponential backoff strategy to watchdog restart (#6262)

supervisor/addons/addon.py

@@ -1562,7 +1562,15 @@ class Addon(AddonModel):
                 )
                 break
 
-            await asyncio.sleep(WATCHDOG_RETRY_SECONDS)
+            # Exponential backoff to spread retries over the throttle window
+            delay = WATCHDOG_RETRY_SECONDS * (1 << max(attempts - 1, 0))
+            _LOGGER.debug(
+                "Watchdog will retry addon %s in %s seconds (attempt %s)",
+                self.name,
+                delay,
+                attempts + 1,
+            )
+            await asyncio.sleep(delay)
 
     async def container_state_changed(self, event: DockerContainerStateEvent) -> None:
         """Set addon state from container state."""