feat: implement CMSG_PET_RENAME with rename dialog in pet frame

- Add PetRenamePacket::build(petGuid, name, isDeclined) builder
- Add GameHandler::renamePet(newName) — sends packet via petGuid_
- Add 'Rename Pet' to pet frame context menu (right-click pet name)
- Modal input dialog with 12-char limit matches server validation

src/game/game_handler.cpp

@@ -14655,6 +14655,14 @@ void GameHandler::dismissPet() {
     socket->send(packet);
 }
 
+void GameHandler::renamePet(const std::string& newName) {
+    if (petGuid_ == 0 || state != WorldState::IN_WORLD || !socket) return;
+    if (newName.empty() || newName.size() > 12) return;  // Server enforces max 12 chars
+    auto packet = PetRenamePacket::build(petGuid_, newName, 0);
+    socket->send(packet);
+    LOG_INFO("Sent CMSG_PET_RENAME: petGuid=0x", std::hex, petGuid_, std::dec, " name='", newName, "'");
+}
+
 void GameHandler::requestStabledPetList() {
     if (state != WorldState::IN_WORLD || !socket || stableMasterGuid_ == 0) return;
     auto pkt = ListStabledPetsPacket::build(stableMasterGuid_);

src/game/world_packets.cpp

@@ -5421,5 +5421,13 @@ network::Packet UnstablePetPacket::build(uint64_t stableMasterGuid, uint32_t pet
     return p;
 }
 
+network::Packet PetRenamePacket::build(uint64_t petGuid, const std::string& name, uint8_t isDeclined) {
+    network::Packet p(wireOpcode(Opcode::CMSG_PET_RENAME));
+    p.writeUInt64(petGuid);
+    p.writeString(name);    // null-terminated
+    p.writeUInt8(isDeclined);
+    return p;
+}
+
 } // namespace game
 } // namespace wowee