[imorland]

Fixes #4939

Changes proposed in this pull request:
The audit ip: filter now matches partial addresses, CIDR ranges and trailing wildcards as well as full addresses, for IPv4 and IPv6 (ip:192.168, ip:10.0.0.0/8, ip:2a02:390:9e5c:beef for its /64). Each entry also stores its address as 32 hex digits of the 16-byte form (IPv4 as IPv4-mapped IPv6) in a new indexed ip_hex column, so every way of writing an IPv6 address matches and a range is an indexed BETWEEN on every driver. Existing entries are indexed by the new php flarum audit:backfill-ip command rather than the migration, so upgrading a large log doesn't stall; until it runs they are still found by exact searches. The search help text shows the new forms.

Reviewers should focus on:

• Hex in a char(32) column instead of a binary column, which avoids binding raw bytes for PostgreSQL bytea and SQLite blobs.
• -ip: now keeps entries that have no IP address (e.g. console actions); before, SQL NOT IN dropped them as a side effect of NULL.
• The migration's down() leaves the column in place, because uninstalling logs extension.uninstalled after rolling migrations back.

Screenshot

Before	After

Necessity

• Has the problem that is being solved here been clearly explained?
• If applicable, have various options for solving this problem been considered?
• For core PRs, does this need to be in core, or could it be in an extension?
• Are we willing to maintain this for years / potentially forever?

Confirmed

• Frontend changes: tested on a local Flarum installation.
• Frontend changes: tests are green (run yarn test in js/).
• Frontend changes: tests have been added, or are not appropriate here.
• Backend changes: tests are green (run composer test).
• Backend changes: tests have been added, or are not appropriate here.
• Where applicable, changes are suitable for all supported database drivers (MySQL, MariaDB, PostgreSQL, SQLite).
• Core developer confirmed locally this works as intended.
• The description above is written by me and describes what this pull request actually does.

Tests pass on SQLite and MariaDB 11.8 (utf8mb4_unicode_ci); PostgreSQL is covered by CI only.

Required changes:

• Related documentation PR: docs(audit): partial address and range search for ip: docs#701