* bucket check and async setup
clients perform direct setup by default
* (python) more consistent json for internal api
all requests and response are JSON.
all binary payloads are explicitly encoded as base64
within api.py, and decoded back to bytes before leaving api.py.
User-facing code, e.g. bucket.py and bucket_service.py,
should not see base64 wrangling.
* Support async for all ops
refactor api.py to be async-first
use new asyncio loops to support non-async interface;
cannot call non-async methods from async context
* [js] update client to work with unified service
bump both versions to 0.2.1
disable npm/pypi publish except on manual workflow run
* disable request compression
* fix workflow tests
update standalone Spiral test server to use new JSON interface
