feat: redesign homepage and early access page

This commit introduces a comprehensive redesign of the homepage and refactors the "Contact Us" page into a dedicated "Get Early Access" page.

Key changes include:
- **Homepage:** A complete overhaul with new sections, including a hero, feature highlights, and a problem/solution section to better communicate the product's value proposition.
- **Early Access Page:** The former "Contact Us" page is now repurposed for early access sign-ups, with updated copy and a more focused call-to-action.
- **Component Refactoring:**
    - The `InputGroup` component has been extracted from the form into a reusable component (`app/_components/InputGroup.tsx`) for better modularity.
    - The `CenterFrame` component has been updated to support images and new props (`src`, `title`, `alt`) to fit the new homepage design.
- **Layout Improvements:** The early access form now uses a two-column grid layout on larger screens for improved user experience.

public/arrow-up.svg

@@ -0,0 +1,3 @@
+<svg width="42" height="26" viewBox="0 0 42 26" fill="none" xmlns="http://www.w3.org/2000/svg">
+<path d="M23.1111 2H40M40 2V19.6M40 2L23.1111 19.6L14.6667 10.8L2 24" stroke="#34BCCB" stroke-width="4" stroke-linecap="round" stroke-linejoin="round"/>
+</svg>