This change extends XMonad.Prompt.Directory by adding a ComplCaseSensitivity field to the Dir constructor, which makes completion case-sensitivity configurable in places where multi-mode prompts only receive a Dir through completionFunction. The author notes that single-mode prompts could support this without an API break, but multi-mode prompts could not, so the constructor had to grow to carry the new setting. For downstream code, this means any direct Dir construction must be updated, but in return prompt completion behavior becomes more flexible and explicit. Practical effect: multi-mode directory prompts can now opt into the right case-sensitivity semantics instead of being locked into one behavior.