netcode-revival: make room/server fields actually apply

Typing a room or relay and pressing Enter did not commit: the fields only
wrote the cvar on ImGuiInputTextFlags_EnterReturnsTrue, and Enter was flaky
in the game. Now:

- Room code commits on every keystroke (uppercase), so the relay follows the
  typed code immediately. A room change re-joins the relay on the next tick
  instead of waiting up to the 5s heartbeat.
- Relay server commits on Enter OR when the field loses focus (clicking
  away), so a swallowed Enter can't leave the old relay active; kept
  commit-on-deactivate (not per keystroke) so partial hostnames don't flap
  the connection while typing.
- Display name commits on change (same Enter flakiness).
- The network loop now splits a 'host:port' server string and uses the
  embedded port for both the relay resolve and the game's netcode transport,
  so typing '127.0.0.1:40001' works (previously it produced a broken
  'host:port:port' resolve).

src/native/skate3_native_ghost.cpp

@@ -733,11 +733,27 @@ void GhostNetworkLoop() {
     }
 
     const bool debug = Debug();
-    const uint16_t port = uint16_t(REXCVAR_GET(skate3_ghost_port));
     std::string server = REXCVAR_GET(skate3_ghost_server);
     if (server.empty()) {
       server = kGhostDefaultServer;
     }
+    // A server string may carry its own port ("host:port"); prefer it over
+    // the port slider so the relay resolve AND the game's netcode transport
+    // agree on the endpoint.
+    std::string host = server;
+    uint16_t port = uint16_t(REXCVAR_GET(skate3_ghost_port));
+    const size_t colon = server.rfind(':');
+    if (colon != std::string::npos && colon != 0 &&
+        colon != server.size() - 1) {
+      host = server.substr(0, colon);
+      try {
+        const int p = std::stoi(server.substr(colon + 1));
+        if (p > 0 && p <= 65535) {
+          port = uint16_t(p);
+        }
+      } catch (...) {
+      }
+    }
     const std::string room_str = REXCVAR_GET(skate3_ghost_room);
     char room_buf[kGhostMaxRoomLen] = {};
     uint8_t room_len = 0;
@@ -754,6 +770,13 @@ void GhostNetworkLoop() {
         g_room_len = room_len;
       }
     }
+    // A typed/clicked room change re-joins the relay on the next tick
+    // instead of waiting up to the heartbeat interval.
+    static std::string s_last_room;
+    if (room_len != 0 && s_last_room != room_str) {
+      s_last_room = room_str;
+      g_peer_public.last_join = 0.0;
+    }
 
     if (sock == GHOST_INVALID_SOCKET) {
       sock = GhostSocketCreate(/*allow_broadcast=*/true);
@@ -768,7 +791,7 @@ void GhostNetworkLoop() {
     if (server != last_server || port != last_port) {
       GhostAddr a;
       g_peer_public.configured =
-          GhostResolve(server + ":" + std::to_string(port), port, &a);
+          GhostResolve(host + ":" + std::to_string(port), port, &a);
       if (g_peer_public.configured) {
         g_peer_public.addr = a;
       } else {
@@ -793,7 +816,7 @@ void GhostNetworkLoop() {
         std::lock_guard<std::mutex> lock(g_mu);
         std::memcpy(active_room, g_room, g_room_len);
       }
-      rex::system::XNetTransport::Instance().SetRelay(server.c_str(), port, active_room);
+      rex::system::XNetTransport::Instance().SetRelay(host.c_str(), port, active_room);
       if (now - g_peer_public.last_join >= kJoinIntervalSec) {
         SendJoin(sock, g_peer_public.addr, /*ping=*/false);
         g_peer_public.last_join = now;

src/skate3_native_ghost_dialog.cpp

@@ -97,11 +97,12 @@ void GhostDialog::OnDraw(ImGuiIO& io) {
   ImGui::Separator();
 
   ImGui::Text("Room code");
+  // Commits on every change so the relay follows the typed code immediately
+  // (no Enter required - Enter was flaky here). Partial codes are harmless:
+  // the relay just moves you to each intermediate room as you type.
   if (ImGui::InputText("##ghost_room", room_input_, sizeof(room_input_),
-                       ImGuiInputTextFlags_EnterReturnsTrue |
+                       ImGuiInputTextFlags_CharsUppercase)) {
-                           ImGuiInputTextFlags_CharsUppercase)) {
     REXCVAR_SET(skate3_ghost_room, std::string(room_input_));
-    ImGui::SetKeyboardFocusHere(-1);
   }
   ImGui::SameLine();
   // Copy the ACTIVE room (the one this player is actually in), which for an
@@ -125,10 +126,8 @@ void GhostDialog::OnDraw(ImGuiIO& io) {
   ImGui::Separator();
 
   ImGui::Text("Display name");
-  if (ImGui::InputText("##ghost_name", name_input_, sizeof(name_input_),
+  if (ImGui::InputText("##ghost_name", name_input_, sizeof(name_input_))) {
-                       ImGuiInputTextFlags_EnterReturnsTrue)) {
     REXCVAR_SET(skate3_ghost_name, std::string(name_input_));
-    ImGui::SetKeyboardFocusHere(-1);
   }
   ImGui::TextDisabled("Shown on your nameplate above the ghost. Empty = "
                       "your OS user name.");
@@ -174,14 +173,16 @@ void GhostDialog::OnDraw(ImGuiIO& io) {
 
   ImGui::Text("Relay server (optional)");
   ImGui::PushItemWidth(-1.0f);
-  if (ImGui::InputText("##ghost_server", server_input_, sizeof(server_input_),
+  // Commit on Enter OR when the field loses focus (clicking away), so a
-                       ImGuiInputTextFlags_EnterReturnsTrue)) {
+  // swallowed Enter cannot leave the old server active. Not commit-on-change:
+  // partial hostnames would flap the connection while typing.
+  ImGui::InputText("##ghost_server", server_input_, sizeof(server_input_));
+  if (ImGui::IsItemDeactivatedAfterEdit()) {
     REXCVAR_SET(skate3_ghost_server, std::string(server_input_));
-    ImGui::SetKeyboardFocusHere(-1);
   }
   ImGui::PopItemWidth();
-  ImGui::TextDisabled("Empty = built-in default relay. No port forwarding "
+  ImGui::TextDisabled("Empty = built-in default relay. Press Enter or click "
-                      "needed on any client.");
+                      "away to apply. No port forwarding needed on any client.");
 
   ImGui::Separator();