Create a Path resolver to apply arnold pathmap to USD paths

**Describe the feature you'd like**
We should create a custom path resolver plugin for USD that allows us to apply [Arnold Path Mapping](https://docs.arnoldrenderer.com/display/A5ARP/Path+Mapping) to the file paths when loading a USD file via the procedural.

We can use [AiResolveFilePath](https://docs.arnoldrenderer.com/api/arnold-6.2.1.1/group__ai__file__utils.html#ga52658744590d18f1a7af187ef3c8f78c) in the resolver plugin.

No file or test is named. Start by locating the USD path-resolver plugin entry point and the procedural's USD-loading path, then read the linked Arnold Path Mapping and AiResolveFilePath documentation. Done means the resolver applies Arnold path mapping when the procedural loads USD file paths, with coverage for the relevant behavior.

Written by the indexing model from the issue text.