chatgui: db_path is now a directory (chat_data/) with chats.db and sync/ inside

- Default db_path changed from 'chats.db' to 'chat_data' directory
- chat_core_init receives <db_path>/chats.db
- db_sync receives <db_path> (creates <db_path>/sync internally)
- Directory auto-created on startup via QDir::mkpath

tools/chatgui/src/main.cpp

@@ -66,9 +66,10 @@ int main(int argc, char *argv[]) {
     }
 
     QString dbPath = cfg.dbPath();
-    if (dbPath.isEmpty()) dbPath = "chats.db";
+    if (dbPath.isEmpty()) dbPath = "chat_data";
     if (!QDir::isAbsolutePath(dbPath))
         dbPath = QCoreApplication::applicationDirPath() + "/" + dbPath;
+    QDir(dbPath).mkpath(".");
 
     DbManager db;
     MainWindow w(nullptr, &db, cfgPath, dbPath, cfg.debugFile(),

tools/chatgui/transport/node_config.cpp

@@ -175,7 +175,7 @@ bool NodeConfig::create(const QString& nodeName, quint16 listenPort) {
     if (listenPort > 0)
         m_servers.append({"lan", QString("0.0.0.0:%1").arg(listenPort)});
     if (m_dbPath.isEmpty())
-        m_dbPath = "chats.db";
+        m_dbPath = "chat_data";
     return save();
 }
 
@@ -340,7 +340,7 @@ bool NodeConfig::save() {
     }
 
     out << "[gui]\n";
-    out << "db_path=" << (m_dbPath.isEmpty() ? "chats.db" : m_dbPath) << "\n";
+    out << "db_path=" << (m_dbPath.isEmpty() ? "chat_data" : m_dbPath) << "\n";
     out << "debug_file=" << m_debugFile << "\n";
     out << "debug_level=" << (m_debugLevel.isEmpty() ? "info" : m_debugLevel) << "\n";
     out << "debug_categories=" << m_debugCategories << "\n\n";

tools/chatgui/transport/utun_node.cpp

@@ -1,6 +1,7 @@
 // utun_node.cpp — embedded uTun node running in a dedicated thread
 #include "utun_node.h"
 #include <cinttypes>
+#include <QDir>
 #include "../../lib/socket_compat.h"
 
 #include "../db/db_manager.h"
@@ -62,6 +63,7 @@ void UtunNode::setDebugFile(const QString& path) {
 
 void UtunNode::setDbPath(const QString& path) {
     m_dbPath = path;
+    QDir(path).mkpath(".");
 }
 
 void UtunNode::setDebugLevel(const QString& level) {
@@ -245,7 +247,7 @@ void UtunNode::runLoop() {
     etcp_router_bind(m_instance, ETCP_RT_ID_CHAT, recvCallback);
 
     /* Initialize chat_core (DB) and chat_sync (channel/message P2P sync) */
-    chat_core_init(m_instance, m_dbPath.toUtf8().constData());
+    chat_core_init(m_instance, QString(m_dbPath + "/chats.db").toUtf8().constData());
     chat_sync_init(m_instance, nullptr);
     chat_sync_auto_connect_start(m_instance);
     DEBUG_INFO(DEBUG_CATEGORY_DEBUG, "chat_core + chat_sync + auto_connect initialized");