Rebase: Make archive detection more robust and add it to the CLI (#1560)

* Rebase/recreate my changes and add MIME support

This commit recreates the changes proposed in #1394 on top of the
current master (b069a2acf1).
This also adds support for determining filetypes using the MIME database
provided by `QMimeDatabase`.

* Move member syntax warning to a more appropriate place

* Deduplicate member syntax warning

* Change warning from "vertical bars" to "|"

* Conform brace placement to coding style

* Fix QFileDialog filter when ArchiveExtensions is empty

* Final cleanup and fixes

- Changes the NDS and GBA ROM MIME-Type constants to QStrings.
- Removes a leftover warning message.
- Uses Type() syntax instead of Type{} syntax for temporaries.

* Explain the origin of the supported archive list

Co-authored-by: Jan Felix Langenbach <insert-penguin@protonmail.com>

src/frontend/qt_sdl/CLI.h

@@ -11,7 +11,7 @@
     melonDS is distributed in the hope that it will be useful, but WITHOUT ANY
     WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
     FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
-    
+
     You should have received a copy of the GNU General Public License along
     with melonDS. If not, see http://www.gnu.org/licenses/.
 */
@@ -22,14 +22,18 @@
 #include <QApplication>
 #include <QStringList>
 
+#include <optional>
+
 namespace CLI {
 
 struct CommandLineOptions
 {
     QStringList errorsToDisplay = {};
 
-    QStringList dsRomPath;
-    QStringList gbaRomPath;
+    std::optional<QString> dsRomPath;
+    std::optional<QString> dsRomArchivePath;
+    std::optional<QString> gbaRomPath;
+    std::optional<QString> gbaRomArchivePath;
     bool fullscreen;
     bool boot;
 };