Initial implementation of Telegram AI customer support bot

Cloudflare Workers + Hono + D1 + KV + R2 stack with 4 specialized AI agents
(onboarding, troubleshoot, asset, billing), OpenAI function calling with
7 tool definitions, human escalation, pending action approval workflow,
feedback collection, audit logging, i18n (ko/en), and Workers AI fallback.

43 source files, 45 tests passing.

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

src/utils/api-urls.ts

@@ -0,0 +1,26 @@
+import type { Env } from '../types';
+
+const DEFAULT_OPENAI_GATEWAY = 'https://gateway.ai.cloudflare.com/v1/d8e5997eb4040f8b489f09095c0f623c/telegram-ai-support/openai';
+const DEFAULT_D2_RENDER_URL = 'http://10.253.100.107:8080';
+
+/**
+ * OpenAI Chat Completions API URL (AI Gateway 경유)
+ */
+export function getOpenAIUrl(env: Env): string {
+  const base = env.OPENAI_API_BASE || DEFAULT_OPENAI_GATEWAY;
+  return `${base}/chat/completions`;
+}
+
+/**
+ * OpenAI API base URL (chat/completions 제외)
+ */
+export function getOpenAIBaseUrl(env: Env): string {
+  return env.OPENAI_API_BASE || DEFAULT_OPENAI_GATEWAY;
+}
+
+/**
+ * D2 diagram rendering service URL
+ */
+export function getD2RenderUrl(env: Env): string {
+  return env.D2_RENDER_URL || DEFAULT_D2_RENDER_URL;
+}