refactor: migrate DataExportSection to PlatformServiceMixin

- Use PlatformServiceMixin for platform and database access
- Replace manual PlatformService instantiation with mixin methods/properties
- Use $contacts() for contact export
- Use capabilities for platform checks in template and logic
- Remove unused imports and redundant code
- Lint clean

src/components/LocationSearchSection.vue

@@ -1,7 +1,7 @@
 <template>
   <section v-if="isRegistered" class="mt-4">
     <h2 class="text-lg font-semibold mb-2">Location for Searches</h2>
-    <div class="mb-2" v-if="searchAreaLabel">
+    <div v-if="searchAreaLabel" class="mb-2">
       <span class="text-slate-700">Current Area: </span>
       <span class="font-mono">{{ searchAreaLabel }}</span>
     </div>
@@ -15,14 +15,14 @@
 </template>
 
 <script lang="ts">
-import { Component, Vue, Prop, Emit } from 'vue-facing-decorator';
+import { Component, Vue, Prop, Emit } from "vue-facing-decorator";
 
-@Component({ name: 'LocationSearchSection' })
+@Component({ name: "LocationSearchSection" })
 export default class LocationSearchSection extends Vue {
   @Prop({ required: true }) isRegistered!: boolean;
   @Prop({ required: false }) searchAreaLabel?: string;
 
-  @Emit('set-search-area')
+  @Emit("set-search-area")
   setSearchArea() {}
 }
-</script> 
+</script>