Implement new Go based Desktop app

This focuses on Windows first, but coudl be used for Mac
and possibly linux in the future.

app/tray/tray_windows.go

@@ -0,0 +1,10 @@
+package tray
+
+import (
+	"github.com/jmorganca/ollama/app/tray/commontray"
+	"github.com/jmorganca/ollama/app/tray/wintray"
+)
+
+func InitPlatformTray(icon, updateIcon []byte) (commontray.OllamaTray, error) {
+	return wintray.InitTray(icon, updateIcon)
+}