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>

scripts/chat-test.sh

@@ -69,14 +69,14 @@ $COMPOSE up -d --wait
 # ── Step 3: Verify server reachable via QUIC ──────────────────────────────────
 
 step "Verifying QUIC connectivity from alice..."
-$COMPOSE exec -T alice quicnprotochat health
+$COMPOSE exec -T alice qpq health
 
 # ── Step 4: Alice — register identity + upload KeyPackage ─────────────────────
 
 step "Alice: register-state..."
-$COMPOSE exec -T alice quicnprotochat register-state --state /chat/alice.bin
+$COMPOSE exec -T alice qpq register-state --state /chat/alice.bin
 
-ALICE_KEY=$($COMPOSE exec -T alice quicnprotochat whoami --state /chat/alice.bin \
+ALICE_KEY=$($COMPOSE exec -T alice qpq whoami --state /chat/alice.bin \
     | grep 'identity_key' | awk '{print $3}' | tr -d '[:space:]')
 info "Alice identity: ${ALICE_KEY}"
 
@@ -88,9 +88,9 @@ fi
 # ── Step 5: Bob — register identity + upload KeyPackage ───────────────────────
 
 step "Bob: register-state..."
-$COMPOSE exec -T bob quicnprotochat register-state --state /chat/bob.bin
+$COMPOSE exec -T bob qpq register-state --state /chat/bob.bin
 
-BOB_KEY=$($COMPOSE exec -T bob quicnprotochat whoami --state /chat/bob.bin \
+BOB_KEY=$($COMPOSE exec -T bob qpq whoami --state /chat/bob.bin \
     | grep 'identity_key' | awk '{print $3}' | tr -d '[:space:]')
 info "Bob identity:   ${BOB_KEY}"
 
@@ -102,21 +102,21 @@ fi
 # ── Step 6: Alice creates group ───────────────────────────────────────────────
 
 step "Alice: create-group 'docker-chat'..."
-$COMPOSE exec -T alice quicnprotochat create-group \
+$COMPOSE exec -T alice qpq create-group \
     --state /chat/alice.bin \
     --group-id docker-chat
 
 # ── Step 7: Alice invites Bob ─────────────────────────────────────────────────
 
 step "Alice: invite Bob..."
-$COMPOSE exec -T alice quicnprotochat invite \
+$COMPOSE exec -T alice qpq invite \
     --state /chat/alice.bin \
     --peer-key "$BOB_KEY"
 
 # ── Step 8: Bob joins ─────────────────────────────────────────────────────────
 
 step "Bob: join group..."
-$COMPOSE exec -T bob quicnprotochat join --state /chat/bob.bin
+$COMPOSE exec -T bob qpq join --state /chat/bob.bin
 
 # ── Step 9: Launch tmux ──────────────────────────────────────────────────────
 
@@ -130,8 +130,8 @@ echo "  Ctrl+D exits a pane."
 echo "  tmux kill-session -t qpc-chat   to stop."
 echo ""
 
-ALICE_CMD="$COMPOSE exec alice quicnprotochat chat --state /chat/alice.bin"
-BOB_CMD="$COMPOSE exec bob quicnprotochat chat --state /chat/bob.bin"
+ALICE_CMD="$COMPOSE exec alice qpq chat --state /chat/alice.bin"
+BOB_CMD="$COMPOSE exec bob qpq chat --state /chat/bob.bin"
 
 # Kill any stale tmux session with the same name.
 tmux kill-session -t qpc-chat 2>/dev/null || true