CivitAI stores non-ASCII file names percent-encoded; the mini endpoint's
raw fileName (preferred since #1100) returned that encoded string, so it
landed on disk literally as "%E7%8A%AC..." and the path-budget
truncation could cut mid-escape. Decode to valid non-ASCII UTF-8 names
before the on-disk name is fixed; literal % (stored as %25) and invalid
escapes pass through unchanged.