feat(mcp): подготовить сервер и доступ к приёмке

components/mcp/artifact-downloads.tsx

@@ -0,0 +1,36 @@
+"use client"
+
+import { useEffect, useRef, useState } from "react"
+import { Button } from "@/components/ui/button"
+import { humanArtifactError, humanArtifactReceipt } from "@/shared/api/mcp-artifact"
+import type { McpApi } from "@/shared/api/mcp"
+
+function ArtifactDownload({ api, receipt }: { api: McpApi; receipt: unknown }) {
+  const [busy, setBusy] = useState(false), [error, setError] = useState(""), [saved, setSaved] = useState(false)
+  const controller = useRef<AbortController | null>(null)
+  useEffect(() => () => controller.current?.abort(), [])
+  const download = async () => {
+    if (controller.current) return
+    const request = new AbortController()
+    controller.current = request
+    setBusy(true); setError(""); setSaved(false)
+    try { await api.downloadArtifact(receipt, request.signal); if (!request.signal.aborted) setSaved(true) }
+    catch (failure) { if (!request.signal.aborted) setError(humanArtifactError(failure)) }
+    finally { if (!request.signal.aborted) setBusy(false); controller.current = null }
+  }
+  return <div className="flex flex-col items-start gap-2">
+    <Button variant="outline" disabled={busy} aria-busy={busy} onClick={() => { void download() }}>{busy ? "Скачивание…" : "Скачать файл"}</Button>
+    {error && <p role="alert" className="text-sm text-destructive">{error}</p>}
+    <p role="status" aria-live="polite" className="text-xs text-muted-foreground">{busy ? "Получаем файл с проверкой доступа…" : saved ? "Файл передан браузеру для сохранения." : "Файл доступен владельцу через авторизацию портала. Срок хранения ограничен."}</p>
+  </div>
+}
+
+export function ArtifactDownloads({ api, operation }: { api: McpApi; operation: Record<string, unknown> }) {
+  if (operation.state !== "applied" || !Array.isArray(operation.artifactReceipts)) return null
+  const receipts = [...new Map(operation.artifactReceipts.flatMap(value => {
+    const receipt = humanArtifactReceipt(value)
+    return receipt ? [[receipt.artifactId, value] as const] : []
+  })).entries()]
+  if (!receipts.length) return null
+  return <div className="flex flex-col gap-3 rounded-md border p-3"><h3 className="text-sm font-medium">Файлы операции</h3>{receipts.map(([id, receipt]) => <ArtifactDownload key={id} api={api} receipt={receipt} />)}</div>
+}