feat: AI assistant panel, editor improvements, vite and package config

editor/composables/useAI.ts

@@ -0,0 +1,18 @@
+export async function sendAIRequest(sessionId: string, userMessage: string, mode: string, apiKey: string): Promise<{ result: string }> {
+  const resp = await fetch('/api/ai', {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({ sessionId, userMessage, apiKey, mode }),
+  })
+  if (!resp.ok) {
+    const err = await resp.json().catch(() => ({ error: 'request failed' }))
+    throw new Error(err.error || 'request failed')
+  }
+  return resp.json()
+}
+
+export async function listSessions(): Promise<any[]> {
+  const resp = await fetch('/api/ai/sessions')
+  if (!resp.ok) return []
+  return resp.json()
+}