The 1.0 Python client, mirroring the Rust client 1.0 API and the DongLoRa Protocol v2 wire format.
* Module split: monolithic protocol.py / client.py replaced with dongle.py (high-level async Dongle), session.py (reader task + tag routing), frame.py (streaming FrameDecoder + encode_frame), commands.py / events.py / errors.py / modulation.py / info.py / crc.py / chip_id (re-export) matching the donglora-protocol Rust crate.
* Async API throughout. Serial I/O via asyncio-serial; mux connections via asyncio streams. The blocking client surface is gone.
* thiserror-equivalent error hierarchy (DongloraError base with Timeout, TransportClosed, ReaderExited, BadFrame, ErrClientError variants mirroring the Rust ClientError).
* Tag-aware dispatch with concurrent in-flight commands: TagAllocator hands out 16-bit device tags, Session routes each response back to the originating coroutine.
* Auto-recovery from ERR(ENOTCONFIGURED): the Dongle caches the last SET_CONFIG and silently re-applies on timeout.
* 500 ms background keepalive task per PROTOCOL.md §3.4.
* Tests rewritten: test_dongle, test_session, test_frame, test_events, test_modulation, test_crc, test_ergonomics; old test_client / test_protocol removed.
* Sticky mux reconnect (from the prior fix commit) is preserved: once a mux socket is in use, reconnects commit to it instead of falling back to USB.
Track mux usage with a module-level flag. Once a mux connection
succeeds, all future connect() calls in the same process only try
the mux. connect() blocks waiting for the socket to reappear;
try_connect() raises immediately so callers can retry with backoff.
swaits
