feat(import): add multi-site import modal and upload-multi API

frontend/src/api/import.ts

@@ -40,6 +40,11 @@ export const uploadCaddyfile = async (content: string): Promise<ImportPreview> =
   return data;
 };
 
+export const uploadCaddyfilesMulti = async (contents: string[]): Promise<ImportPreview> => {
+  const { data } = await client.post<ImportPreview>('/import/upload-multi', { contents });
+  return data;
+};
+
 export const getImportPreview = async (): Promise<ImportPreview> => {
   const { data } = await client.get<ImportPreview>('/import/preview');
   return data;

frontend/src/components/ImportSitesModal.tsx

@@ -0,0 +1,90 @@
+import React, { useState } from 'react'
+import { uploadCaddyfilesMulti } from '../api/import'
+
+type Props = {
+  visible: boolean
+  onClose: () => void
+  onUploaded?: () => void
+}
+
+export default function ImportSitesModal({ visible, onClose, onUploaded }: Props) {
+  const [sites, setSites] = useState<string[]>([''])
+  const [loading, setLoading] = useState(false)
+  const [error, setError] = useState<string | null>(null)
+
+  if (!visible) return null
+
+  const setSite = (index: number, value: string) => {
+    const s = [...sites]
+    s[index] = value
+    setSites(s)
+  }
+
+  const addSite = () => setSites(prev => [...prev, ''])
+  const removeSite = (index: number) => setSites(prev => prev.filter((_, i) => i !== index))
+
+  const handleSubmit = async () => {
+    setError(null)
+    setLoading(true)
+    try {
+      const cleaned = sites.map(s => s || '')
+      await uploadCaddyfilesMulti(cleaned)
+      setLoading(false)
+      onUploaded && onUploaded()
+      onClose()
+    } catch (err: any) {
+      setError(err?.message || 'Upload failed')
+      setLoading(false)
+    }
+  }
+
+  return (
+    <div className="fixed inset-0 z-50 flex items-center justify-center">
+      <div className="absolute inset-0 bg-black/60" onClick={onClose} />
+      <div className="relative bg-dark-card rounded-lg p-6 w-[900px] max-w-full">
+        <h3 className="text-xl font-semibold text-white mb-4">Multi-site Import</h3>
+        <p className="text-gray-400 text-sm mb-4">Add each site's Caddyfile content separately, then parse them together.</p>
+
+        <div className="space-y-4 max-h-[60vh] overflow-auto mb-4">
+          {sites.map((s, idx) => (
+            <div key={idx} className="border border-gray-800 rounded-lg p-3">
+              <div className="flex justify-between items-center mb-2">
+                <div className="text-sm text-gray-300">Site {idx + 1}</div>
+                <div>
+                  {sites.length > 1 && (
+                    <button
+                      onClick={() => removeSite(idx)}
+                      className="text-red-400 text-sm hover:underline mr-2"
+                    >
+                      Remove
+                    </button>
+                  )}
+                </div>
+              </div>
+              <textarea
+                value={s}
+                onChange={e => setSite(idx, e.target.value)}
+                placeholder={`example.com {\n  reverse_proxy localhost:8080\n}`}
+                className="w-full h-48 bg-gray-900 border border-gray-700 rounded-lg p-3 text-white font-mono text-sm"
+              />
+            </div>
+          ))}
+        </div>
+
+        {error && <div className="bg-red-900/20 border border-red-500 text-red-400 px-4 py-2 rounded mb-4">{error}</div>}
+
+        <div className="flex gap-3 justify-end">
+          <button onClick={addSite} className="px-4 py-2 bg-gray-800 text-white rounded">+ Add site</button>
+          <button onClick={onClose} className="px-4 py-2 bg-gray-700 text-white rounded">Cancel</button>
+          <button
+            onClick={handleSubmit}
+            disabled={loading}
+            className="px-4 py-2 bg-blue-active text-white rounded disabled:opacity-60"
+          >
+            {loading ? 'Processing...' : 'Parse and Review'}
+          </button>
+        </div>
+      </div>
+    </div>
+  )
+}

frontend/src/pages/ImportCaddy.tsx

@@ -2,11 +2,13 @@ import { useState } from 'react'
 import { useImport } from '../hooks/useImport'
 import ImportBanner from '../components/ImportBanner'
 import ImportReviewTable from '../components/ImportReviewTable'
+import ImportSitesModal from '../components/ImportSitesModal'
 
 export default function ImportCaddy() {
   const { session, preview, loading, error, upload, commit, cancel } = useImport()
   const [content, setContent] = useState('')
   const [showReview, setShowReview] = useState(false)
+  const [showMultiModal, setShowMultiModal] = useState(false)
 
   const handleUpload = async () => {
     if (!content.trim()) {
@@ -138,6 +140,12 @@ api.example.com {
             >
               {loading ? 'Processing...' : 'Parse and Review'}
             </button>
+            <button
+              onClick={() => setShowMultiModal(true)}
+              className="ml-4 px-4 py-2 bg-gray-800 text-white rounded-lg"
+            >
+              Multi-site Import
+            </button>
           </div>
         </div>
       )}
@@ -153,6 +161,12 @@ api.example.com {
           onCancel={() => setShowReview(false)}
         />
       )}
+
+      <ImportSitesModal
+        visible={showMultiModal}
+        onClose={() => setShowMultiModal(false)}
+        onUploaded={() => setShowReview(true)}
+      />
     </div>
   )
 }