chore: rename quicproquo → quicprochat in Rust workspace

Rename all crate directories, package names, binary names, proto
package/module paths, ALPN strings, env var prefixes, config filenames,
mDNS service names, and plugin ABI symbols from quicproquo/qpq to
quicprochat/qpc.

sdks/python/quicprochat/__init__.py

@@ -0,0 +1,38 @@
+"""quicproquo -- Python SDK for the quicproquo E2E encrypted messenger.
+
+Two transport backends are available:
+
+1. **FFI** (``QpqClient.connect_ffi``): wraps the Rust ``libquicproquo_ffi``
+   shared library via CFFI.  This gives you the full Rust crypto stack
+   (MLS, hybrid KEM, OPAQUE) at native speed.
+
+2. **QUIC** (``QpqClient.connect``): pure-Python QUIC transport via *aioquic*
+   with protobuf (v2 wire format).  No Rust dependency required; crypto
+   operations must be supplied externally.
+"""
+
+from quicproquo.client import QpqClient
+from quicproquo.types import (
+    ConnectOptions,
+    Envelope,
+    ChannelResult,
+    HealthInfo,
+    QpqError,
+    AuthError,
+    TimeoutError as QpqTimeoutError,
+    ConnectionError as QpqConnectionError,
+)
+
+__version__ = "0.1.0"
+
+__all__ = [
+    "QpqClient",
+    "ConnectOptions",
+    "Envelope",
+    "ChannelResult",
+    "HealthInfo",
+    "QpqError",
+    "AuthError",
+    "QpqTimeoutError",
+    "QpqConnectionError",
+]