fix: skip GPU/mode overlays when extension base compose_file is missing

resolve-compose-stack.sh included GPU overlay files (compose.nvidia.yaml,
compose.amd.yaml) even when the base compose_file declared in the manifest
did not exist on disk. This caused silent Docker Compose merge failures
because the GPU overlay expects services defined in the base file.

Add an else guard: if compose_file is specified but missing (and no
.disabled sibling exists), log a warning and skip all overlays for that
extension.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: yasinBursali

dream-server/scripts/resolve-compose-stack.sh

@@ -168,6 +168,9 @@ if ext_dir.exists():
                     resolved.append(str(compose_path.relative_to(script_dir)))
                 elif (service_dir / f"{compose_rel}.disabled").exists():
                     continue  # Service disabled — skip all overlays
+                else:
+                    print(f"WARNING: {service_dir.name}: compose_file '{compose_rel}' not found, skipping overlays", file=sys.stderr)
+                    continue  # Base compose missing — skip GPU/mode overlays
             # GPU-specific overlay (filesystem discovery — not in manifest)
             gpu_overlay = service_dir / f"compose.{gpu_backend}.yaml"
             if gpu_overlay.exists():