[FEA]: Ability to provide an extra path for cuda-pathfinder to search with high priority

Is this a duplicate?

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Area

cuda.pathfinder

Is your feature request related to a problem? Please describe.

The cuda-pathfinder's search path prioritizes libraries from wheels. For example, libnvshmem_host.so comes from libnvidia-nvshmem-cuXX wheel. If I'm working from a development branch of nvshmem, I may need to manually copy libraries over the site-packages directory in order to get my custom libraries to be opened. LD_LIBRARY_PATH is much lower in the priority order (on purpose), so that won't work either.

Describe the solution you'd like

A few different ideas come to mind:

• <LIBNAME_UPPER_CASE>_PATH_OVERRIDE so each library has an ability to be overridden independently
• CUDA_PATHFINDER_TOP_PRIORITY_PATH which applies to all pathfinder searches
• Adding a <library>_HOME environment variable, and prioritizing it above other search paths

Describe alternatives you've considered

I think I listed all 3 above. The current hacky WAR is to copy .so files around on the system.

Additional context

No response