Add file uploads and refresh ShareModal and UserMenu

[PanchoutNathan]

Summary

• Add reusable file upload components with single and multiple file modes.
• Support uploading, completed, and error states with optional error details.
• Prevent layout shifts when hovering rows or dragging files.
• Integrate selected users directly into the ShareModal search field.
• Keep the search icon and first row fixed when selected users wrap across multiple lines.
• Refresh the UserMenu layout, spacing, colors, icons, and actions.
• Add Storybook examples and functional component tests.
• Improve Storybook dependency pre-bundling to prevent dynamic import errors.