Track Chatto v0.5.0-beta.11

The only delta between v0.5.0-beta.10 and v0.5.0-beta.11 is
metadata-only: two comment expansions in chatto.api.v1 (the
UpdateMessage doc now spells out that message.manage permits removal of
another author's channel echo while only the author can enable one, and
PushNotificationService.Subscribe notes that a stored push subscription
expires 180 days after its most recent save and the client owns the
refresh). No fields, RPCs, oneof members, or protocol versions changed,
so the regenerated _pb/ bindings are byte-identical and the client
required no code adaptation.

Verification: ruff format/check clean; mypy zero new errors vs the
pre-change baseline (the 6 pre-existing import-untyped protobuf
errors are unchanged); pytest 92 passed, 2 skipped (live bot
integration tests); live GetServer round-trip against
https://chat.chatto.run OK; live bot integration tests
(test_bot_receives_its_own_message, test_public_server_metadata) passed
against the real server.

Bumped version 0.5.0b10 -> 0.5.0b11.

proto/chatto/api/v1/messages.proto

@@ -263,8 +263,10 @@ service MessageService {
   // thread or reject a thread placement that the mode does not allow.
   rpc CreateMessage(CreateMessageRequest) returns (CreateMessageResponse);
   // Edits a message body. Authors can edit their own messages within the edit
-  // window. Effective message.manage permits edits at any time. Only the
-  // message author can change channel echo state. Disabled rooms reject
+  // window. Effective message.manage permits edits at any time and removal of
+  // another author's channel echo. Only the author can enable an echo, which
+  // also requires message.echo and message.post. Omit unchanged echo state.
+  // Disabled rooms reject
   // creation of a new channel echo while allowing an existing echo to be
   // removed. Room membership is also required.
   // Edits require message.read or a matching thread relationship with

proto/chatto/api/v1/push_notifications.proto

@@ -10,6 +10,11 @@ service PushNotificationService {
   //
   // The server must have Web Push configured. Clients normally call this after
   // the browser grants notification permission and returns a PushSubscription.
+  // A stored subscription expires 180 days after its most recent save. The
+  // client owns the refresh: call Subscribe again when the app starts and at
+  // least once a day while it runs, and when the browser replaces the
+  // PushSubscription. The server removes expired records itself. Call
+  // Unsubscribe to stop delivery before the subscription expires.
   rpc Subscribe(SubscribeRequest) returns (SubscribeResponse);
 
   // Removes the caller's browser push subscription by endpoint.

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "chattolib"
-version = "0.5.0b10"
+version = "0.5.0b11"
 description = "Async Python client library for the Chatto webchat Connect API"
 requires-python = ">=3.11"
 license = "MPL-2.0 AND Apache-2.0"