docs(filters): document In List, Include / Exclude and Paste List

[Maffooch]

Description

Documents three list filters on the Pro UI's Filter Index page: In List / Not in List on text filters, the Include / Exclude switch on multi-select filters, and Paste List on the Asset and Organization filters. None of them was documented. The page also states the practical size limit on list filters and the Filter Too Long message a user sees past it.

Pairs with a Pro change that makes these filters fast on large tenants and adds the size guard. Docs only, no code changes.

🤖 Generated with Claude Code

[Maffooch]

Moving this to 3.4.300. The "Long lists" section documents DefectDojo-Inc/dojo-pro#4300, which has moved to 3.4.300, and docs PRs merge only after the Pro change they describe. Also worth sorting out before it merges: #16359, #16366 and #16370 are still open and edit PRO__filter_index.md to document the same filters, so one set should be closed.

[blakeaowens]

Superseded by #16406, which documents the reworked list filters (In List / Not in List on text filters, Include / Exclude, In List of names on the Asset and Organization filters, and the size limit) in one change.