refactor(admin): split evidence, import, portfolio pages

Extract components and hooks from oversized pages into colocated
_components/ and _hooks/ subdirectories to enforce the 500-LOC hard cap.
page.tsx files reduced to 205, 121, and 136 LOC respectively.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

admin-compliance/app/sdk/import/_components/UploadZone.tsx

@@ -0,0 +1,100 @@
+'use client'
+
+import { useState, useCallback } from 'react'
+
+export function UploadZone({
+  onFilesAdded,
+  isDisabled,
+}: {
+  onFilesAdded: (files: File[]) => void
+  isDisabled: boolean
+}) {
+  const [isDragging, setIsDragging] = useState(false)
+
+  const handleDragOver = useCallback((e: React.DragEvent) => {
+    e.preventDefault()
+    if (!isDisabled) setIsDragging(true)
+  }, [isDisabled])
+
+  const handleDragLeave = useCallback((e: React.DragEvent) => {
+    e.preventDefault()
+    setIsDragging(false)
+  }, [])
+
+  const handleDrop = useCallback(
+    (e: React.DragEvent) => {
+      e.preventDefault()
+      setIsDragging(false)
+      if (isDisabled) return
+      const files = Array.from(e.dataTransfer.files).filter(
+        f => f.type === 'application/pdf' || f.type.startsWith('image/')
+      )
+      if (files.length > 0) onFilesAdded(files)
+    },
+    [onFilesAdded, isDisabled]
+  )
+
+  const handleFileSelect = useCallback(
+    (e: React.ChangeEvent<HTMLInputElement>) => {
+      if (e.target.files && !isDisabled) {
+        onFilesAdded(Array.from(e.target.files))
+      }
+    },
+    [onFilesAdded, isDisabled]
+  )
+
+  return (
+    <div
+      onDragOver={handleDragOver}
+      onDragLeave={handleDragLeave}
+      onDrop={handleDrop}
+      className={`relative border-2 border-dashed rounded-xl p-12 text-center transition-all ${
+        isDisabled
+          ? 'border-gray-200 bg-gray-50 cursor-not-allowed'
+          : isDragging
+          ? 'border-purple-500 bg-purple-50'
+          : 'border-gray-300 hover:border-purple-400 hover:bg-purple-50/50 cursor-pointer'
+      }`}
+    >
+      <input
+        type="file"
+        accept=".pdf,image/*"
+        multiple
+        onChange={handleFileSelect}
+        disabled={isDisabled}
+        className="absolute inset-0 w-full h-full opacity-0 cursor-pointer disabled:cursor-not-allowed"
+      />
+      <div className="flex flex-col items-center gap-4">
+        <div className={`w-16 h-16 rounded-full flex items-center justify-center ${isDragging ? 'bg-purple-100' : 'bg-gray-100'}`}>
+          <svg
+            className={`w-8 h-8 ${isDragging ? 'text-purple-600' : 'text-gray-400'}`}
+            fill="none"
+            stroke="currentColor"
+            viewBox="0 0 24 24"
+          >
+            <path
+              strokeLinecap="round"
+              strokeLinejoin="round"
+              strokeWidth={2}
+              d="M7 16a4 4 0 01-.88-7.903A5 5 0 1115.9 6L16 6a5 5 0 011 9.9M15 13l-3-3m0 0l-3 3m3-3v12"
+            />
+          </svg>
+        </div>
+        <div>
+          <p className="text-lg font-medium text-gray-900">
+            {isDragging ? 'Dateien hier ablegen' : 'Dokumente hochladen'}
+          </p>
+          <p className="mt-1 text-sm text-gray-500">
+            Ziehen Sie PDF-Dateien hierher oder klicken Sie zum Auswaehlen
+          </p>
+        </div>
+        <div className="flex items-center gap-2 text-xs text-gray-400">
+          <span>Unterstuetzte Formate:</span>
+          <span className="px-2 py-0.5 bg-gray-100 rounded">PDF</span>
+          <span className="px-2 py-0.5 bg-gray-100 rounded">JPG</span>
+          <span className="px-2 py-0.5 bg-gray-100 rounded">PNG</span>
+        </div>
+      </div>
+    </div>
+  )
+}