feat: dual time zones, autostart, tray icon, config relocation, tests

- Dual clock (primary/secondary time zone) with IANA picker, persisted in XML
- AutoStartManager: macOS LaunchAgent (com.clouck.clock, RunAtLoad)
- Tray icon: template image, light/dark adaptation, toggle + quit menu
- ConfigManager: default path moved to QStandardPaths::AppConfigLocation
- Qt Test suite (ConfigManager, AutoStartManager) wired into CTest
- GitHub origin renamed to upstream; private Gitea repo as origin

config_manager.cpp

@@ -1,6 +1,10 @@
 #include "config_manager.h"
+#include <QDir>
 #include <QFile>
+#include <QFileInfo>
 #include <QDebug>
+#include <QStandardPaths>
+#include <QTimeZone>
 
 ConfigManager::ConfigManager(QObject *parent)
     : QObject(parent)
@@ -8,9 +12,27 @@ ConfigManager::ConfigManager(QObject *parent)
     setDefaultValues();
 }
 
+QString ConfigManager::defaultSettingsPath()
+{
+    const QString configDirectory = QStandardPaths::writableLocation(QStandardPaths::AppConfigLocation);
+    if (configDirectory.isEmpty())
+    {
+        qWarning() << "No application configuration directory is available";
+        return QString();
+    }
+
+    return QDir(configDirectory).filePath("config.xml");
+}
+
 bool ConfigManager::loadSettings(const QString &filename)
 {
-    QFile file(filename);
+    const QString settingsPath = filename.isEmpty() ? defaultSettingsPath() : filename;
+    if (settingsPath.isEmpty())
+    {
+        return false;
+    }
+
+    QFile file(settingsPath);
     if (!file.exists())
     {
         qDebug() << "Config file does not exist, using defaults";
@@ -77,6 +99,14 @@ bool ConfigManager::loadSettings(const QString &filename)
                 m_windowSize = QSize(width, height);
             }
         }
+        else if (name == "PrimaryTimeZone")
+        {
+            m_primaryTimeZoneId = text;
+        }
+        else if (name == "SecondaryTimeZone")
+        {
+            m_secondaryTimeZoneId = text;
+        }
         else
         {
             reader.skipCurrentElement();
@@ -96,7 +126,20 @@ bool ConfigManager::loadSettings(const QString &filename)
 
 bool ConfigManager::saveSettings(const QString &filename)
 {
-    QFile file(filename);
+    const QString settingsPath = filename.isEmpty() ? defaultSettingsPath() : filename;
+    if (settingsPath.isEmpty())
+    {
+        return false;
+    }
+
+    const QFileInfo fileInfo(settingsPath);
+    if (!QDir().mkpath(fileInfo.absolutePath()))
+    {
+        qDebug() << "Cannot create configuration directory:" << fileInfo.absolutePath();
+        return false;
+    }
+
+    QFile file(settingsPath);
     if (!file.open(QIODevice::WriteOnly | QIODevice::Text))
     {
         qDebug() << "Cannot open config file for writing:" << file.errorString();
@@ -134,6 +177,9 @@ bool ConfigManager::saveSettings(const QString &filename)
                           .arg(m_windowSize.height());
     writer.writeTextElement("WindowSize", sizeStr);
 
+    writer.writeTextElement("PrimaryTimeZone", m_primaryTimeZoneId);
+    writer.writeTextElement("SecondaryTimeZone", m_secondaryTimeZoneId);
+
     // Close root element
     writer.writeEndElement();
 
@@ -150,13 +196,14 @@ void ConfigManager::resetToDefaults()
 
 bool ConfigManager::configExists(const QString &filename) const
 {
-    return QFile::exists(filename);
+    const QString settingsPath = filename.isEmpty() ? defaultSettingsPath() : filename;
+    return !settingsPath.isEmpty() && QFile::exists(settingsPath);
 }
 
 void ConfigManager::setDefaultValues()
 {
-    m_fontColor = QColor(255, 255, 255);      // White
-    m_backgroundColor = QColor(0, 0, 0, 150); // Semi-transparent black
+    m_fontColor = QColor(0, 255, 0);
+    m_backgroundColor = QColor(0, 0, 0, 0);
     m_fontSize = 24;
     m_alwaysOnTop = true;
 
@@ -164,5 +211,7 @@ void ConfigManager::setDefaultValues()
     // Position will be set properly when widget is shown for the first time
     m_windowPosition = QPoint(-1, -1); // Special value indicating "not set yet"
 
-    m_windowSize = QSize(200, 80); // Default clock size
+    m_windowSize = QSize(240, 160); // Default clock size
+    m_primaryTimeZoneId = QString::fromUtf8(QTimeZone::systemTimeZoneId());
+    m_secondaryTimeZoneId = QStringLiteral("America/Los_Angeles");
 }