feat!: v0.2.0 — module split, Rust parity, PyPI-ready

Split monolithic __init__.py into six modules matching the Rust client
structure: protocol.py, codec.py, discovery.py, transport.py, connect.py,
client.py. All symbols re-exported from top-level for backwards compat.

New features:
- Ping-on-connect validation (200ms handshake, matches Rust v0.2.0)
- try_connect(), connect_default(), connect_mux_auto(), validate()
- connect() commits to mux when socket exists (no USB fall-through)
- Bandwidth/ErrorCode IntEnums, RadioConfig TypedDict, py.typed marker
- MAX_PAYLOAD, RADIO_CONFIG_SIZE, tag/error constants
- Payload size validation on Transmit
- 46 pytest tests ported from Rust (protocol, codec, client, firmware compat)
- GitHub Actions CI (ruff + pytest on 3.10-3.13 + PyPI publish)
- Strict ruff linting (E, W, F, I, UP, B, C4, ARG, SIM, RUF)

Breaking: package renamed back to donglora (from donglora-python).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -0,0 +1,53 @@
+# Changelog
+
+## 0.2.0 — 2026-04-08
+
+### Features
+
+- **Module split matching Rust structure** — split monolithic `__init__.py` into
+  `protocol.py`, `codec.py`, `discovery.py`, `transport.py`, `connect.py`, and
+  `client.py`. All symbols re-exported from top-level for backwards compatibility.
+- **Ping-on-connect validation** — all connect functions automatically ping the
+  device and reject non-DongLoRa devices within 200 ms (matches Rust v0.2.0).
+- **`try_connect(timeout)`** — non-blocking alternative to `connect()`. Returns
+  an error immediately if no device is found.
+- **`connect_default()`** — convenience wrapper with default timeout.
+- **`connect_mux_auto(timeout)`** — mux-only connection, never falls back to USB
+  serial. Equivalent of Rust client's "sticky mux" behaviour.
+- **`default_socket_path()`** — resolve the preferred mux socket path.
+- **`validate(ser)`** — public function for manual device validation.
+- **Payload size validation** — `encode_command("Transmit", ...)` rejects
+  payloads exceeding 256 bytes.
+- **`Bandwidth` and `ErrorCode` enums** — `IntEnum` types matching the Rust
+  definitions.
+- **`RadioConfig` TypedDict** — typed dict for radio configuration.
+- **New constants** — `MAX_PAYLOAD`, `RADIO_CONFIG_SIZE`, `CMD_TAG_*`,
+  `RESP_TAG_*`, `ERROR_*` tag/error constants.
+- **`py.typed` marker** — PEP 561 support for type checkers.
+- **Comprehensive test suite** — 46 tests ported from the Rust client covering
+  protocol roundtrips, COBS framing, client send/recv, firmware wire
+  compatibility.
+- **GitHub Actions CI** — ruff lint + format, pytest on Python 3.10–3.13, PyPI
+  publish on tag.
+- **Strict ruff linting** — E, W, F, I, UP, B, C4, ARG, SIM, RUF rules.
+
+### Breaking changes
+
+- **Package renamed back to `donglora`** — the short-lived `donglora-python`
+  name is reverted. Import as `import donglora` (was always the intended API).
+- **`connect()` no longer falls through from mux to USB serial** — if a mux
+  socket file exists, the function commits to the mux or raises an error
+  (matches Rust v0.2.1). This prevents port-stealing race conditions.
+- **Sticky mux global removed** — the module-level `_mux_mode` variable and
+  `_reconnect_mux()` are gone. Use `connect_mux_auto()` for mux-only mode.
+- **`DEFAULT_CONFIG` now includes `cad: 1`** — previously relied on
+  `encode_config()` defaulting it.
+
+### Fixes
+
+- Fixed broken dependency paths that prevented `uv sync` from resolving.
+- Replaced `print()` calls with `logging` in discovery module.
+
+## 0.1.0 — 2026-04-06
+
+Initial release.