Updated importer icons

[snipe]

It's come up a few times that the importer icon/visual language is a little unclear. This PR attempts to rectify that with hopefully clearer icons and descriptive tooltips.

Before

After

[shortcut-integration]

This pull request has been linked to Shortcut Story #24322: Import icons/buttons are a bit confusing.

[what-the-diff]

PR Summary

• Improved User Interface Localization
  The file resources/lang/en/general.php now includes a new translation string import_this_file. This change means that more parts of our application can support different languages, thus improving user experience for non-English speakers.

• Updated Menu Item Icon
  The icon for the 'imports' menu item, located in resources/views/layouts/default.blade.php, has been changed from a 'download cloud' (fa-cloud-download-alt) symbol to an 'upload cloud' (fa-cloud-upload-alt) symbol. This alteration better represents the function of the menu item, making the application easier to navigate for users.

• Enhanced Import Button Aesthetics and Functionality
  The 'import' button in resources/views/livewire/importer.blade.php has undergone two updates. The icon has switched from a 'retweet' (fa-retweet) to a 'check list' (fa-list-check), and a tooltip has been added. These modifications will not only make the button's purpose more intuitive but will also help users understand what action will be performed when the button is clicked.