Context:
Task T414592 resolved an issue where dash-separated IP ranges (e.g. "X.X.X.X - Y.Y.Y.Y") caused undefined index warnings in ContributionsRangeTrait. The task was intentionally resolved by treating such input as invalid to avoid introducing new behavior.

Motivation:
Dash-separated IP ranges appear on various on-wiki pages (e.g. abuse reports, noticeboards, SPI reports). It may be useful to define how such input should be handled by MediaWiki input components.

Topics for discussion:

1. Should MediaWiki accept dash-separated IPv4/IPv6 ranges as valid input?
2. Should they be normalized internally (e.g. to CIDR) where possible?
3. Which components should participate (HTMLUserTextField, Contributions, Special:Block, etc.)?
4. How should CIDR enforcement rules interact with ranges?
5. How should invalid or mixed IPv4/IPv6 ranges be handled?

Note:
This is intentionally separate from T414592 to avoid mixing a bug fix with a behavioral change. cc @Dreamy_Jazz