Padding LoRA ranks to enable merging

I'm quite shaky on the math, but would it be possible to pad a lower rank LoRA (with zeros, or something else) in order to merge a lower rank LoRA with a higher rank?

I've been playing with SVD distillation at 256 rank, and might want to merge in a trained LoRA, but don't have the time or resources to fully train a high rank LoRA.

No files, tests, or entry points are identified in the issue. First trace how LoRA ranks and merging are handled, then establish whether zero-padding preserves the intended result when combining different ranks. Done would require a decided approach and a demonstrated merge for the stated lower- and higher-rank cases.

Written by the indexing model from the issue text.