feat(`@vtmn/css`, `@vtmn/svelte`): switch `VtmnIcon` to svg

[Tlahey]

Changes description

BREAKING CHANGES !

Closes #1445

Context

Checklist

• [ ] Make sure you are requesting to pull a topic/feature/bugfix branch. Please, don't request directly from your main!
• [ ] Check commits & PR names matches our requested structure. It must follow the https://www.conventionalcommits.org pattern.
• [ ] Check your code additions will fail neither code linting checks.
• [ ] I have reviewed the submitted code.
• [ ] I have tested on related showcases.
• [ ] If it includes design changes, please ask for a review design-system-core-team-design GitHub team.

Does this introduce a breaking change?

• Yes

Other information