fix: replace defines with constexpr/const and use more absolute paths for includes (#5527)

bye bye nuuls

src/singletons/ImageUploader.cpp

@@ -24,11 +24,11 @@
 
 #include <utility>
 
-#define UPLOAD_DELAY 2000
-// Delay between uploads in milliseconds
-
 namespace {
 
+// Delay between uploads in milliseconds
+constexpr int UPLOAD_DELAY = 2000;
+
 std::optional<QByteArray> convertToPng(const QImage &image)
 {
     QByteArray imageData;