feat: implement create-chat-conversation function with OpenAI integration and Supabase support

- Added CORS handling for the create-chat-conversation function.
- Implemented health check endpoint for the function.
- Created endpoints for managing conversations and messages with OpenAI.
- Added error handling and response formatting for better API usability.
- Introduced utility functions for environment variable management and Supabase client creation.
- Enhanced schema handling for structured responses from OpenAI.
- Implemented conversation archiving and retrieval logic.

supabase/functions/create-chat-conversation/lib/supabase.ts

@@ -0,0 +1,30 @@
+import { createClient } from "jsr:@supabase/supabase-js";
+import { mustGetEnv } from "./env.ts";
+import { HttpError } from "./errors.ts";
+
+export function getSupabaseServiceClient() {
+  const url = mustGetEnv("SUPABASE_URL");
+  const key = mustGetEnv("SUPABASE_SERVICE_ROLE_KEY");
+  return createClient(url, key, { auth: { persistSession: false } });
+}
+
+export function getSupabaseAnonClient(authHeader?: string) {
+  const url = mustGetEnv("SUPABASE_URL");
+  const key = mustGetEnv("SUPABASE_ANON_KEY");
+  return createClient(url, key, {
+    auth: { persistSession: false },
+    global: authHeader ? { headers: { Authorization: authHeader } } : undefined,
+  });
+}
+
+export async function requireUser(authHeader?: string) {
+  if (!authHeader) {
+    throw new HttpError(401, "missing_auth", "Missing Authorization header");
+  }
+  const anon = getSupabaseAnonClient(authHeader);
+  const { data, error } = await anon.auth.getUser();
+  if (error || !data?.user) {
+    throw new HttpError(401, "invalid_auth", "Invalid or expired token", error);
+  }
+  return data.user;
+}