chore: rename project quicnprotochat -> quicproquo (binaries: qpq)

Rename the entire workspace:
- Crate packages: quicnprotochat-{core,proto,server,client,gui,p2p,mobile} -> quicproquo-*
- Binary names: quicnprotochat -> qpq, quicnprotochat-server -> qpq-server,
  quicnprotochat-gui -> qpq-gui
- Default files: *-state.bin -> qpq-state.bin, *-server.toml -> qpq-server.toml,
  *.db -> qpq.db
- Environment variable prefix: QUICNPROTOCHAT_* -> QPQ_*
- App identifier: chat.quicnproto.gui -> chat.quicproquo.gui
- Proto package: quicnprotochat.bench -> quicproquo.bench
- All documentation, Docker, CI, and script references updated

HKDF domain-separation strings and P2P ALPN remain unchanged for
backward compatibility with existing encrypted state and wire protocol.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

crates/quicproquo-mobile/Cargo.toml

@@ -0,0 +1,23 @@
+[package]
+name        = "quicproquo-mobile"
+version     = "0.1.0"
+edition     = "2021"
+description = "C FFI layer for quicproquo, proving QUIC connection migration."
+license     = "MIT"
+
+[lib]
+crate-type = ["staticlib", "cdylib", "rlib"]
+
+[dependencies]
+# Async
+tokio     = { workspace = true }
+
+# QUIC
+quinn     = { workspace = true }
+rustls    = { workspace = true }
+
+# Error handling
+anyhow    = { workspace = true }
+
+[dev-dependencies]
+rcgen = { workspace = true }