[✨] Modify head at runtime with useDocumentHead

[GrandSchtroumpf]

Is your feature request related to a problem?

I want to update the head content dynamically from a hook. I've got a theme picker and want to update the theme-color meta tag.
From what I understand this is currently impossible to update head properties at runtime.

Describe the solution you'd like

Two options :

1. useDocumentHead().meta can be a Signal.
2. useDocumentHead() could provide an update method.

I would rather use option 1.

Describe alternatives you've considered

Use the DOM api, but then it wouldn't work on the server.

Additional context

No response

[ahnpnl]

I have another alternative is, you can create a global context and update context in component. In RouterHead, you can react to the context change to set meta tag value and combine with existing meta tags from useDocumentHead, inspired by this https://robisim74.gitbook.io/qwik-speak/library/quick-start#head-metas

[gioboa]

We moved this issue to qwik-evolution repo to create a RFC discussion for this.
Here is our Qwik RFC process thanks.