feat: form blocks design

[elianiva]

it should be relatively easy since we'll use https://www.shadcn-svelte.com/ for the UI

although tests are still needed to check for the functionality

some of the blocks that i could think of:

• text input block
• long text input block (paragraph, etc)
• radio input block
• checkbox input block
• select input block
• time input block
• date input block
• linear scale input block