[Leo] - Update to limited / unlimited - lock indicators for freemium and premium models

[aguscruiz]

Description

Updated the indicators of freemium / premium models in Leo.
Indicator in the header label for premium remains as is.

Test Plan

For both the menu in the sidebar and on the settings page

• Only the premium model should have a special label ("Premium") and only for non-premium users

Before

• Freemium models used limited / unlimited labels
• Premium models used a lock / open lock icon

Updated to

• Freemium models show limited only for free users. Premium users don't see a label
• Premium models show premium label for free users. Premium users don't see a label

Figma file:

https://www.figma.com/file/m0Gdbf0wtqyfEFGm32VLLc/Leo?type=design&node-id=1653-76695&mode=design

[mattmcalister]

The updated version makes sense. Let's go with that.