HeadlessUI v2

[lishaduck]

Description

This PR migrates to HeadlessUI v2.
HeadlessUI v2 has floating-ui built in, which should really help the menus in the header.
It also ships with a checkbox and other components for forms.
Finally, it supports list virtualization.

---

Type of Change

• 🗑️ Chore

Checklist

Checklist

Beta Give feedback

1. Read the Contributing Guidelines.
2. Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
3. Fill out this template.
4. Log your hours.
5. Check that commits follow the Angular commit convention, more or less.
6. Ideally, include relevant tests that fail without this PR but pass with it (if applicable).

Tested on

• macOS 14

[lishaduck]

Ok. After investigation, this works! 🚀
However, it requires DENO_FUTURE=1. This isn't set be default (Deno 2 is still some time away), and you can't set it on Deno Deploy. There is no workaround. 😞
As it stands, I guess we'll just wait for a response to denoland/fresh#2206 (comment) or denoland/deno#23784.