[message-buffer 10/X] - Message Buffer Admin IXs & variable length (#779)
* ok
* ok
* it runs
* add this stuff
* working on tests
* feat(message-buffer): finish create_buffer ix, update put_all
* feat: rename bufferheader to messageBuffer, add delete_buffer impl
* feat(message-buffer): remove unused code, add additional checks, update unit tests
* style(message-buffer): fix pre-commit, run fmt & clippy
* fix(message-buffer): add verification checks, fix ts test
* refactor(message-buffer): rename update_whitelist_authority to admin
* fix(message-buffer): address PR comments
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Co-authored-by: Jayant Krishnamurthy <jayantkrishnamurthy@gmail.com>