🐛 Fix: isFocused devtools warning

[tyler-dane]

Closes #284

This pull request introduces several changes to the packages/web project, focusing on the addition of an IconProvider component, refactoring of icon-related code, and minor improvements to the event form's date pickers.

Icon Provider and Related Refactoring:

• Added a new IconProvider component to manage icon context and size (packages/web/src/components/IconProvider/IconProvider.tsx).
• Wrapped RootRouter with IconProvider in the App component (packages/web/src/App.tsx). [1] [2]
• Simplified iconStyles by removing the isFocused prop and using IconProps instead (packages/web/src/components/Icons/styled.ts).
• Updated various icon usages to remove the size and isFocused props, utilizing the new IconProvider for consistent icon sizing and color management (packages/web/src/views/Calendar/components/Dedication/Dedication.tsx, packages/web/src/views/Calendar/components/Header/Header.tsx, packages/web/src/views/Calendar/components/Sidebar/SidebarIconRow/SidebarIconRow.tsx). [1] [2] [3] [4]

Minor Improvements:

• Improved readability by refactoring conditional statements in DatePickers component (packages/web/src/views/Forms/EventForm/DateTimeSection/DatePickers/DatePickers.tsx). [1] [2]
• Removed unused useRef import from DateTimeSection component (packages/web/src/views/Forms/EventForm/DateTimeSection/DateTimeSection.tsx).

These changes enhance the consistency and maintainability of the icon usage across the application and improve the code quality in the event form components.