Implement new UI component for icons #230

- Introduce `AppIcon.vue`, offering improved performance over the
  previous `fort-awesome` dependency. This implementation reduces bundle
  size by 67.31KB (tested for web using `npm run build -- --mode prod`).
- Migrate Font Awesome 5 icons to Font Awesome 6.

This commit facilitates migration to Vue 3.0 (#230) and ensures no Vue
component remains tightly bound to a specific Vue version, enhancing
code portability.

Font Awesome license is not included because Font Awesome revokes its
right:

> "Attribution is no longer required as of Font Awesome 3.0"
>
> Sources:
>
> - https://fontawesome.com/v4/license/ (archived: https://web.archive.org/web/20231003213441/https://fontawesome.com/v4/license/, https://archive.ph/Yy9j5)
> - https://github.com/FortAwesome/Font-Awesome/wiki (archived: https://web.archive.org/web/20231003214646/https://github.com/FortAwesome/Font-Awesome/wiki, https://archive.ph/C6sXv)

This commit removes following third-party production dependencies:

- `@fortawesome/vue-fontawesome`
- `@fortawesome/free-solid-svg-icons`
- `@fortawesome/free-regular-svg-icons`
- `@fortawesome/free-brands-svg-icons`
- `@fortawesome/fontawesome-svg-core`

src/presentation/assets/icons/file-arrow-down.svg

@@ -0,0 +1 @@
+<!-- Source: Font Awesome 6 --><svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 384 512"><path d="M64 0C28.7 0 0 28.7 0 64V448c0 35.3 28.7 64 64 64H320c35.3 0 64-28.7 64-64V160H256c-17.7 0-32-14.3-32-32V0H64zM256 0V128H384L256 0zM216 232V334.1l31-31c9.4-9.4 24.6-9.4 33.9 0s9.4 24.6 0 33.9l-72 72c-9.4 9.4-24.6 9.4-33.9 0l-72-72c-9.4-9.4-9.4-24.6 0-33.9s24.6-9.4 33.9 0l31 31V232c0-13.3 10.7-24 24-24s24 10.7 24 24z"/></svg>