…15094)

resolves coder/internal#176

This is a proof of concept to showcase the use of Tailwind + shadcn/ui.
The goal here was to implement a lower complexity page to reduce the
initial risk and highlight the specific global changes needed.

Changes:

- Create a separate version of Premium features content for Enterprise
and OSS users
- Use shadcn/ui button component and setup styling and variants to match
the buttons defined in the Coder Kit Figma.
https://www.figma.com/design/WfqIgsTFXN2BscBSSyXWF8/Coder-kit?node-id=3-1756
- Setup theming using CSS variables and custom Tailwind colors by using
the dark class name on the root element.
- CSS variable design token naming and colors defined in Figma.
https://www.figma.com/design/WfqIgsTFXN2BscBSSyXWF8/Coder-kit?node-id=1-2


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<img width="1197" alt="Screenshot 2024-11-01 at 12 45 36 PM"
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