DEV: allows to disable strip_whitespaces in messages (#26848)

The TextCleaner step has been moved from chat message’s validation to create_message/update_message services. It allows us to easily tweak part of its behavior depending on the needs.

For example we will now disable strip_whitespaces by default when streaming messages as we want to keep newlines and spaces at the end of the message.

plugins/chat/lib/chat_sdk/message.rb

@@ -37,7 +37,7 @@ module ChatSDK
     #
     # @see #create
     def self.create_with_stream(**params, &block)
-      self.create(**params, streaming: true, &block)
+      self.create(**params, streaming: true, strip_whitespaces: false, &block)
     end
 
     # Streams to a specific chat message.
@@ -114,6 +114,7 @@ module ChatSDK
       streaming: false,
       enforce_membership: false,
       force_thread: false,
+      strip_whitespaces: true,
       &block
     )
       message =
@@ -128,6 +129,7 @@ module ChatSDK
           streaming: streaming,
           enforce_membership: enforce_membership,
           force_thread: force_thread,
+          strip_whitespaces: strip_whitespaces,
         ) do
           on_model_not_found(:channel) { raise "Couldn't find channel with id: `#{channel_id}`" }
           on_model_not_found(:channel_membership) do
@@ -179,6 +181,7 @@ module ChatSDK
         message: self.message.message + raw,
         guardian: self.guardian,
         streaming: true,
+        strip_whitespaces: false,
       ) { on_failure { raise "Unexpected error" } }
 
       self.message