* framed_{write,read}: dynamic max_message_size

* experimental libbacktrace support

* do not build git target if it is already exists

* coroutines: detach now logs failed coroutines by default

* coroutines use-after-free bugfix

* Context.h: get returns reference and CHECKS that current context is not null

* fix CE

* fix co_return {}

* clang format

* add libbacktrace as submodule

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Co-authored-by: birydrad <>