fix: detect CD images once, pass into createBundle

CD-only games were failing because the second findCdImages() call
inside createBundle returned empty. Now detection happens once in
the upload method and the result is passed to createBundle.

src/main/java/com/dostalgia/UploadResource.java

@@ -82,10 +82,13 @@ public class UploadResource {
 
             // Find main executable
             String mainExe = findMainExe(extractDir);
+
+            // Detect CD images once (used for both CD-only detection and config generation)
+            List<String> cdImages = findCdImages(extractDir);
+
             if (mainExe == null) {
                 // No executable on the filesystem — check if CD images exist instead
-                List<String> cdOnlyImages = findCdImages(extractDir);
-                if (cdOnlyImages.isEmpty()) {
+                if (cdImages.isEmpty()) {
                     return Response.status(400)
                         .entity(Map.of("error", "No executable (.exe/.com/.bat) found in the archive"))
                         .build();
@@ -103,7 +106,7 @@ public class UploadResource {
             // Create .jsdos bundle inside the game directory
             String bundleFile = gameId + "/" + gameId + ".jsdos";
             Path bundlePath = gameDir.resolve(gameId + ".jsdos");
-            createBundle(extractDir, mainExe, bundlePath);
+            createBundle(extractDir, mainExe, cdImages, bundlePath);
 
             // Detect platform (DOS vs Windows) by reading the main EXE header
             String platform = mainExe != null ? detectPlatform(Path.of(mainExe)) : "dos";
@@ -441,12 +444,10 @@ public class UploadResource {
         "zoo", "arc", "ha", "cab"                  // others
     );
 
-    private void createBundle(Path extractDir, String exePath, Path bundlePath) throws IOException {
+    private void createBundle(Path extractDir, String exePath, List<String> cdImages, Path bundlePath) throws IOException {
         // Write .jsdos config directly into the extract directory
         Path jsdos = extractDir.resolve(".jsdos");
         Files.createDirectories(jsdos);
-        // Find CD images for DOSBox imgmount (mountable via D:, E:, …)
-        List<String> cdImages = findCdImages(extractDir);
         if (exePath != null) {
             String relExe = extractDir.relativize(Path.of(exePath)).toString();
             Files.writeString(jsdos.resolve("dosbox.conf"), buildDosboxConf(relExe, cdImages));