fix: pre-stage linuxdeploy plugins; add wrapper diagnostic log

tools/ld_wrapper.c

@@ -12,15 +12,13 @@ int main(int argc, char **argv) {
     snprintf(apprun, sizeof(apprun), "%s/AppRun", appdir);
     snprintf(ldbin, sizeof(ldbin), "%s/usr/bin/linuxdeploy", appdir);
 
-    /* Strip --appimage-extract-and-run: that's an AppImage runtime flag,
-       not a linuxdeploy flag. Passing it to the real binary causes immediate failure. */
+    /* Strip --appimage-extract-and-run: AppImage runtime flag, not a linuxdeploy flag */
     char **new_argv = malloc((argc + 1) * sizeof(char *));
     int new_argc = 0;
     new_argv[new_argc++] = argv[0];
     for (int i = 1; i < argc; i++) {
-        if (strcmp(argv[i], "--appimage-extract-and-run") != 0) {
+        if (strcmp(argv[i], "--appimage-extract-and-run") != 0)
             new_argv[new_argc++] = argv[i];
-        }
     }
     new_argv[new_argc] = NULL;
 
@@ -35,9 +33,21 @@ int main(int argc, char **argv) {
              appdir, appdir, old_ldpath ? old_ldpath : "");
     setenv("LD_LIBRARY_PATH", new_ldpath, 1);
 
-    if (stat(ldbin, &st) == 0) {
-        execv(ldbin, new_argv);
+    /* Write diagnostic log visible in the always() post-step */
+    FILE *log = fopen("/tmp/ld-wrapper.log", "w");
+    if (log) {
+        fprintf(log, "APPDIR=%s\n", appdir);
+        fprintf(log, "AppRun exists: %s\n", stat(apprun, &st) == 0 ? "yes" : "NO");
+        fprintf(log, "linuxdeploy exists: %s\n", stat(ldbin, &st) == 0 ? "yes" : "NO");
+        fprintf(log, "argc=%d new_argc=%d\n", argc, new_argc);
+        fprintf(log, "args:");
+        for (int i = 0; i < new_argc; i++) fprintf(log, " [%s]", new_argv[i]);
+        fprintf(log, "\nPATH=%s\n", getenv("PATH") ? getenv("PATH") : "(null)");
+        fclose(log);
     }
+
+    if (stat(ldbin, &st) == 0)
+        execv(ldbin, new_argv);
     execv(apprun, new_argv);
     return 1;
 }