fix: add stub ImportDialog, unblock vite build

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/components/common/ImportDialog.vue

@@ -0,0 +1,36 @@
+<script setup lang="ts">
+import { ref } from "vue";
+
+const visible = ref(false);
+
+function open() {
+  visible.value = true;
+}
+
+function close() {
+  visible.value = false;
+}
+
+defineExpose({ open });
+</script>
+
+<template>
+  <Teleport to="body">
+    <div v-if="visible" class="fixed inset-0 z-50 flex items-center justify-center bg-black/60" @click.self="close">
+      <div class="bg-zinc-800 border border-zinc-700 rounded-xl shadow-2xl p-6 w-[400px]">
+        <h2 class="text-lg font-semibold text-zinc-100 mb-4">Import Connections</h2>
+        <p class="text-sm text-zinc-400 mb-6">
+          Import is not available in this version. Add connections manually via the sidebar.
+        </p>
+        <div class="flex justify-end">
+          <button
+            class="px-4 py-2 text-sm bg-zinc-700 hover:bg-zinc-600 text-zinc-200 rounded-lg"
+            @click="close"
+          >
+            Close
+          </button>
+        </div>
+      </div>
+    </div>
+  </Teleport>
+</template>