now polling for changes returns span and text so that it's possible to
edit just the changed region. greatly improved controller internal api
with crate-level traits keeping error handling localized
instead of storing cursors it just streams them as they happen. instead
of just getting cursors from the controller, now you also send your
operations into it, mimicking more the behavior used for text ops
note that there's an awful OP_CACHE set to store our edits because we
get them as events too... will have a ton of edge cases! apart from this
text synchronization works pretty well, also autocompletions
actually the stopping channel doesn't fit super well inside the
OperationController itself since the tasks are handled above that
abstraction layer, but storing it inside makes my life incredibly
simpler so im gonna do that for now
added some const functions to calculate leading and tailing noops, made
apply() and process() return Range<u64>. actors implementation is still
awful but will do them properly in the future
move features and tools into codemp library, trying to decouple stuff
from nvim. also implemented a proper outgoing queue and operation
composing, making connections more reliable
now everything that worked in 0.2 seems to work again, and should
actually be better. plus, merging differences is done properly and thus
should be way more reliable
