refactor: add must_use to event loop handles

CHANGELOG.md

@@ -23,6 +23,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - OTA: Allow specifying image size to speed up erase
 - Bluetooth: New methods `EspBleGap::start_scanning` and `EspBleGap::stop_scanning`
 - New example, `bt_ble_gap_scanner` to demonstrate usage of added ble scanning methods
+- Add #[must_use] annotations to event loop types with drop handlers.
 
 ## [0.51.0] - 2025-01-15
 

src/eventloop.rs

@@ -331,6 +331,7 @@ where
     }
 }
 
+#[must_use = "Event subscription is unregistered when handle is dropped"]
 pub struct EspSubscription<'a, T>
 where
     T: EspEventLoopType,
@@ -486,6 +487,7 @@ where
     }
 }
 
+#[must_use = "Event loop is deleted when handle is dropped"]
 #[derive(Debug)]
 struct EventLoopHandle<T>(T)
 where