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/components/Shared/Modal/ModalDialog.vue

@@ -10,9 +10,7 @@
         class="dialog__close-button"
         @click="hide"
       >
-        <font-awesome-icon
-          :icon="['fas', 'times']"
-        />
+        <AppIcon icon="xmark" />
       </div>
     </div>
   </ModalContainer>
@@ -20,11 +18,13 @@
 
 <script lang="ts">
 import { defineComponent, computed } from 'vue';
+import AppIcon from '@/presentation/components/Shared/Icon/AppIcon.vue';
 import ModalContainer from './ModalContainer.vue';
 
 export default defineComponent({
   components: {
     ModalContainer,
+    AppIcon,
   },
   emits: {
     /* eslint-disable @typescript-eslint/no-unused-vars */