Deduplicate filing types by unique filing type code, not EFSP code

[nonprofittechy]

See SuffolkLITLab/LITEFile#134

It looks like, from digging in efiling proxy server code, the only thing that matters is the filing code when the case is filed, so that internal identifier can be ignored.

(unless this changes upstream in EFilingProxyServer first)

[BryceStevenWilley]

Going to move this to the proxy server, it needs to be fixed there. If we don't just remove those dupes from the database entirely (I might, I'm so tired of this ridiculousness), at least our APIs shouldn't be returning dupes

[nonprofittechy]

Additional live partner-testing confirmation from Vermont LITEFile (laptop + Chrome):

• @VTskier The Filing Type choices need deduplication; the tester saw multiple entries with the same user-facing name, including multiple Affidavit choices.

This looks like the same class of problem tracked here rather than a new LITEFile-only dropdown issue. LITEFile currently consumes the filing-type list from the proxy and sorts/prioritizes it; it should not have to distinguish duplicate rows that represent the same effective filing code.

Cross-reference: SuffolkLITLab/LITEFile#8 previously tracked duplicate Filing Type UI choices and was closed, so this report is useful evidence that deduplication needs to be durable at the proxy/code layer.

Please include a regression case with duplicate EFSP/internal identifiers mapping to the same effective filing type code/name when implementing this.