Record Linux native preview and desktop suite results

docs/ROADMAP.md

@@ -61,6 +61,8 @@ release. Keep their evidence and unchecked production gates intact.
 - [ ] Validate native custom-protocol image/audio/video playback and seeking on
   release platforms; structural Windows CPU tests alone do not close this gate.
   See [preview contract and evidence](MEDIA-PREVIEW.md).
+  - [x] Linux WSL native Rust preview tests (9/9) and full desktop suite (45/45)
+    passed on the immutable implementation snapshot; actual playback remains open.
 - [x] Official single-instance transport with isolated explicit profiles;
   Windows CPU duplicate launch exits without a second query worker.
   See [launch evidence](SINGLE-INSTANCE.md); visual focus and other OS checks remain open.