Paving the way to remove `ExcerptId`. Done in this PR: - Unshipped the stack trace view - Get rid of `push_excerpts` - Get rid of some callers of `remove_excerpts` We still need to remove some calls to `remove_excerpts` and other APIs, especially in `randomly_edit_excerpts` and collaboration. Release Notes: - The stack trace multibuffer view has been removed. --------- Co-authored-by: Conrad Irwin <conrad.irwin@gmail.com>