fix: pack no launcher file the emulator installs

The launcher layer packed a file under the launcher's name whatever the
platform installs: ROCKNIX's xemu config reads hdd/xbox_hdd.qcow2, and
the profile marks that image installed_on rocknix, yet the pack brought
one. A place whose entry the emulator installs on that platform is now
filled by the install, as validation.deliverable has it for the pack.

scripts/launchers.py

@@ -399,6 +399,11 @@ class LauncherLayer:
                 return True
             if not place.anchored:
                 continue
+            # The emulator as this platform installs it brings the file: the
+            # place is filled, nothing is packed (ROCKNIX's xemu hdd image).
+            if any(key in candidate.names and report.get("bundled")
+                   for candidate, report in matched):
+                return True
             source = self._content_for(place, name, key, matched, resolve_held)
             if source is None:
                 continue