⚖️ Clarify released asset notices

THIRD_PARTY_NOTICES.md

@@ -1,11 +1,15 @@
 # Third-party notices
 
-- NavOL policy checkpoints were trained using NavDP model initialization and
-  retain any applicable upstream model terms.
+- `models/navdp-cross-modal.ckpt` is the NavDP initialization checkpoint used
+  by NavOL training and retains the applicable upstream model terms.
+- NavOL policy checkpoints were trained using that initialization and retain
+  any applicable upstream model terms.
+- `robots/dingo.usd` retains the terms and attribution requirements of its
+  upstream robot-asset source.
 - NavOL integrates with Isaac Lab. Isaac Lab-originated source files retain
   their BSD 3-Clause headers.
-- Benchmark meshes, materials, and textures retain the terms and attribution
-  requirements of their original scene and material sources.
+- Training and benchmark meshes, materials, and textures retain the terms and
+  attribution requirements of their original scene and material sources.
 - Vendored `rsl_rl` and `torchinterp1d` components retain the license files in
   their respective source directories.