Reverse token filter mangles strings that contain combining characters

Reverse token filter mangles strings that contain combining characters: a task in MiMo-V2.6-RL-harbor-code: MiMo-V2.6-RL Code (Harbor) (Harbor dataset). I'm using the reverse token filter as part of an analyzer chain to index text in a few languages that make heavy use of diacritics (think…

The task

I'm using the `reverse` token filter as part of an analyzer chain to index text in a few languages that make heavy use of diacritics (think Vietnamese, or French/Spanish text that ends up in NFD form after some upstream normalization). The idea is to reverse the token so I can do suffix-style matching.

Part of FineEnvs/MiMo-V2.6-RL-harbor-code.