Change tray icon so it is the right color on MacOS

## Summary

On MacOS the system tray icon is off-color because it uses the gray-colored `kdeconnectindicatordark` icon which does not match the rest of MacOS.

![image](/uploads/430933399d9570dc1c59807e4715e87b/image.png)

BUG: 430226

I've used two patches to fix this:
1. Always use the status `KStatusNotifierItem::Passive` on MacOS. `KStatusNotifierItem` will only mark the icon as a mask (which is needed to allow it to dynamically switch between light and dark theme) [if the status is passive](https://invent.kde.org/frameworks/knotifications/-/blob/cff7c337ab9a78708ac5594badb54e8f88f61a8d/src/kstatusnotifieritem.cpp#L1079-1081).
2. The above should theoretically be enough to fix the issue and I swear at one point it was all that was needed. However, to fix this issue in my dev environment I also needed to pass in a `QIcon` with `setIsMask(true)` instead of setting the icon by its name. And I also use the `kdeconnectindicator` instead of `kdeconnectindicatordark` icon.

## Test Plan

The icon now renders in the correct color, regardless of whether devices are connected:

![image](/uploads/5010a07cbb5f23a286ece641c6b3879c/image.png) ![image](/uploads/2ae5d3d8aa633ebafb260febe313057c/image.png)

## Future work

Once I've verified this PR is working in the right direction, I want to look into making the icon gray (and hopefully a much easier-to-see gray) when no devices are connected!

For example, WireGuard, when not connected, looks like this:

![image](/uploads/43c2ef6bc7261431e878c9c1c05174f9/image.png) ![image](/uploads/f7587190648606df77ad3e3dde84098f/image.png)

P.S. I've been testing off the v21.12.2 tag since the master branch doesn't compile for me, so I haven't tested this change on the latest dev commit. But there should be no conflicts.

indicator/indicatorhelper_mac.cpp

@@ -127,7 +127,9 @@ void IndicatorHelper::systrayIconHook(KStatusNotifierItem &systray)
 {
     const QString iconPath = QStandardPaths::locate(QStandardPaths::AppDataLocation, QStringLiteral("kdeconnect-icons"), QStandardPaths::LocateDirectory);
     if (!iconPath.isNull()) {
-        systray.setIconByName(QStringLiteral("kdeconnectindicatordark"));
+        auto icon = QIcon::fromTheme(QStringLiteral("kdeconnectindicator"));
+        icon.setIsMask(true); // Make icon adapt to menu bar color
+        systray.setIconByPixmap(icon);
     } else {
         // We are in macOS dev env, just continue
         qWarning() << "Fail to find indicator icon, continue anyway";

indicator/main.cpp

@@ -162,7 +162,9 @@ int main(int argc, char** argv)
     systray.setStandardActionsEnabled(false);
     QObject::connect(&model, &DevicesModel::rowsChanged, &model, [&systray, &model]() {
         const auto count = model.rowCount();
+#ifndef Q_OS_MACOS // On MacOS, setting status to Active disables color theme syncing of the menu icon
         systray.setStatus(count == 0 ? KStatusNotifierItem::Passive : KStatusNotifierItem::Active);
+#endif
         systray.setToolTip(QStringLiteral("kdeconnect"), QStringLiteral("KDE Connect"), i18np("%1 device connected", "%1 devices connected", count));
     });