Rust view server doesn't correctly attribute source info to swap claim outputs

[hdevalence]

Describe the bug

Consider the output in https://github.com/penumbra-zone/penumbra/pull/3883#issuecomment-1963390213

The 100gm should be marked as having source the same address as the others, since it was the output of a swap I made. Instead it's unattributed.

(Fixing this seems low priority at the moment, but worth noting for later).