Document asset region profile runtime selection

Author: sheikh-nv

docs/source/setup/installation/asset_caching_details.inc

@@ -75,8 +75,8 @@ root resolves to the same value when you use one of the provided Isaac Lab exper
 load ``isaacsim.storage.native``. A custom experience that does not build on one of them may leave the
 Isaac Sim asset root pointing at the cloud.
 
-The environment variable is the only supported runtime override for the Isaac Lab asset paths. Isaac Lab
-resolves them once, when :mod:`isaaclab.utils.assets` is imported, so setting
+Isaac Lab supports the ``ISAACSIM_ASSET_ROOT`` and ``ISAACSIM_ASSET_REGION_PROFILE`` environment variables
+for runtime asset selection. It resolves asset paths once, when :mod:`isaaclab.utils.assets` is imported, so setting
 ``persistent.isaac.asset_root.default`` on the command line or changing it at runtime does not move them,
 even though Isaac Sim itself honors those forms. Editing ``persistent.isaac.asset_root.default`` in the
 experience file does work, because that is the value Isaac Lab reads when the variable is unset.