Clear release notes

RELEASE_NOTES.md

@@ -2,48 +2,16 @@
 
 ## Summary
 
-This release improves the `BaseApiClient` interface and introduces HTTP2 keep-alive, among other changes.
+<!-- Here goes a general summary of what this release is about -->
 
 ## Upgrading
 
-- `GrpcStreamBroadcaster` now takes a `AsyncIterable` instead of a `AsyncIterator` as the `stream_method`. This is to match the type of streaming methods generated by `grpc`, so no conversion to an `AsyncIterator` is needed.
+<!-- Here goes notes on how to upgrade from previous versions, including deprecations and what they should be replaced with -->
 
-- `GrpcStreamBroadcaster` no longer tries to reconnect when a server closes a connection.  This behaviour can be overridden by passing `retry_on_exhausted_stream=True` when constructing `GrpcStreamBroadcaster` instances.
-
-- gRPC URLs don't have a default port anymore, unless a default is set via `ChannelOptions`. If you want to set a default port for URLs, please pass custom `ChannelOptions` as `defaults` to `parse_grpc_uri` or as `channel_defaults` to `BaseApiClient`.
-
-* The `ExponentialBackoff` and `LinearBackoff` classes now require keyword arguments for their constructor. This change was made to make the classes easier to use and to avoid confusion with the order of the arguments.
-
-- HTTP2 keep-alive is now enabled by default, with an interval of 60 seconds between pings, and a 20 second timeout for responses from the service.  These values are configurable and may be updated based on specific requirements.
-
-* The `BaseApiClient` class is not generic anymore, and doesn't take a function to create the stub. Instead, subclasses should create their own stub right after calling the parent constructor. This enables subclasses to cast the stub to the generated `XxxAsyncStub` class, which have proper `async` type hints. To convert you client:
-
-    ```python
-    # Old
-    from my_service_pb2_grpc import MyServiceStub
-    class MyApiClient(BaseApiClient[MyServiceStub]):
-        def __init__(self, server_url: str, *, ...) -> None:
-            super().__init__(server_url, MyServiceStub, ...)
-            ...
-
-    # New
-    from typing import cast
-    from my_service_pb2_grpc import MyServiceStub, MyServiceAsyncStub
-    class MyApiClient(BaseApiClient):
-        def __init__(self, server_url: str, *, ...) -> None:
-            super().__init__(server_url, connect=connect)
-            self._stub = cast(MyServiceAsyncStub, MyServiceStub(self.channel))
-            ...
-
-        @property
-        def stub(self) -> MyServiceAsyncStub:
-            if self._channel is None:
-                raise ClientNotConnected(server_url=self.server_url, operation="stub")
-            return self._stub
-    ```
+## New Features
 
-    After this, you should be able to remove a lot of `cast`s or `type: ignore` from the code when calling the stub `async` methods.
+<!-- Here goes the main new features and examples or instructions on how to use them -->
 
-## New Features
+## Bug Fixes
 
-- Added support for HTTP2 keep-alive.
+<!-- Here goes notable bug fixes that are worth a special mention or explanation -->