feat: add shared metadata editor + flexible modal component

[Benzilla]

Description

• Adds a shared metadata editor component, as many objects allow for metadata editing within the dashboard. Have added it to prices and products so far, and also updated the inline metadata editor in product form to use it.
• Created a share modal component that can be used for popup modals and passing and html into it (like slide-panel). Updated confirm-dialogue to basically be a wrapper around this.
• Removed icons.scss file as this duplicated global styles in styles.scss.

Type of Change

• Bug fix
• New feature
• Breaking change
• Refactoring
• Documentation

How Was This Tested?

• Unit tests
• Integration tests
• Manual testing

Tested adding, editing and deleting metadata.

Checklist

• Self-reviewed my code
• No new warnings
• Existing tests still pass