Promote AgentCompany-New to the repository root and retire the old app

The legacy application - its src, tests, landing site, promo assets, docs,
release tooling, CI workflows, and root configs - leaves the tree; it stays
reachable in history. Everything under AgentCompany-New moves up unchanged:
same package name, so the production userData/database path is untouched,
and e2e/build scripts already resolved paths relative to the project. The
developer cred.txt stays gitignored at its new location. Full verify:ci
passes from the new root.

src/main/services/provider-response-utils.ts

@@ -0,0 +1,38 @@
+import { createHash } from "node:crypto";
+
+export function hashPrompt(prompt: string): string {
+  return createHash("sha256").update(prompt).digest("hex");
+}
+
+export function readProviderResponseId(rawResponseJson: string): string | null {
+  const parsed = JSON.parse(rawResponseJson) as unknown;
+  if (!isRecord(parsed)) return null;
+  const id = parsed.id;
+  return typeof id === "string" && id.trim() ? id.trim() : null;
+}
+
+export function readProviderFailureMessage(rawResponseJson: string, status: string): string {
+  const parsed = JSON.parse(rawResponseJson) as unknown;
+  if (!isRecord(parsed)) return `Provider background response ended with status ${status}.`;
+  const error = parsed.error;
+  if (typeof error === "string" && error.trim()) return error.trim();
+  if (isRecord(error) && typeof error.message === "string" && error.message.trim()) return error.message.trim();
+  const incomplete = parsed.incomplete_details;
+  if (isRecord(incomplete) && typeof incomplete.reason === "string" && incomplete.reason.trim()) return incomplete.reason.trim();
+  return `Provider background response ended with status ${status}.`;
+}
+
+export function requireStreamText(parts: string[]): string {
+  const text = parts.join("");
+  if (!text.trim()) throw new Error("Provider stream returned no text content.");
+  return text;
+}
+
+export function requireBackgroundText(text: string | null, providerKey: string): string {
+  if (!text?.trim()) throw new Error(`${providerKey} background response returned no text content.`);
+  return text;
+}
+
+function isRecord(value: unknown): value is Record<string, unknown> {
+  return typeof value === "object" && value !== null && !Array.isArray(value);
+}