FastAuth v0.8.1

Fixed

• Authentication no longer blocks the event loop. Every route and dependency
  that hashes a password or queries the database was declared async def,
  which meant FastAPI ran it on the event loop: a single login held the whole
  process for the duration of its bcrypt verification (roughly 200ms), and
  every authenticated request blocked the loop for the length of its user
  lookup. Concurrent logins queued behind one another and stalled unrelated
  traffic. Those handlers are now synchronous, so FastAPI runs them in a
  threadpool. No API changes: request and response shapes are identical, and
  throughput under concurrency improves substantially.