introduced the `Modal` component and implemented the necessary boilerplate with the modal provider/context
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Linear Task: [[ https://linear.app/comm/issue/ENG-1953/implement-investor-directory-page-design | ENG-1953 ]]
Figma: [[ https://www.figma.com/file/HAAQwcEIjM32gnEMy2d0k5/Comm-%2F-Landing?node-id=2710%3A36047 | Investor Page ]]
Depends on D5328