Change Details

Now that existing message specs each have a `canBeSidebarSource` method, I need to update the function `isInvalidSidebarSource` to check `messageSpec.canBeSidebarSource`. Addresses Part 1c of [[ https://linear.app/comm/issue/ENG-4849/thread-from-robotext-about-pinned-message-causing-errors | ENG-4849 ]] Depends on D9325

Now that existing message specs each have a `canBeSidebarSource` method, I need to update the function `isInvalidSidebarSource` to check `messageSpec.canBeSidebarSource`. Resolves https://linear.app/comm/issue/ENG-5209/update-isinvalidsidebarsource-to-check-messagespeccanbesidebarsource Depends on D9325

Now that existing message specs each have a `canBeSidebarSource` method, I need to update the function `isInvalidSidebarSource` to check `messageSpec.canBeSidebarSource`. Addresses Part 1c of [[ https://linear.app/comm/issue/ENG-4849/thread-from-robotext-about-pinned-message-causing-errors | ENG-4849 ]]Resolves https://linear.app/comm/issue/ENG-5209/update-isinvalidsidebarsource-to-check-messagespeccanbesidebarsource Depends on D9325