Channel modes +v and +o

[mpan-pl]

Adding missing +v and +o modes, as per observation from #libera (around 2025-07-24 10:36 UTC).

yamllint: ✓
hunspell: ✓
jekyll: not tested (incompatible version)

Contribution released into the public domain (per CC0-1.0).

[TheDaemoness]

I'm not a fan of the "matching users" terminology because status modes are not list modes and don't "match" anything. They're set on a channel for specific users only as long as said users are in that channel. They cannot be set on a range of users (without client shenanigans) nor can they be set ahead of time.

Explaining what a status mode is would probably call for alterations to content/_guides/channelmodes.md. I'm willing to write such an explanation; let me know if you'd prefer that.

[mpan-pl]

I was unaware I’m the one that has to accept aaronmdjones’s request, and that the lack of my acceptance is blocking this PR for so long. Fixed now.