finalised client APIs and authentication method

server/api/v1/client/auth/callback/index.post.ts

@@ -0,0 +1,20 @@
+import clientHandler from "~/server/internal/clients/handler";
+
+export default defineEventHandler(async (h3) => {
+  const userId = await h3.context.session.getUserId(h3);
+  if (!userId) throw createError({ statusCode: 403 });
+
+  const body = await readBody(h3);
+  const clientId = await body.id;
+
+  const data = await clientHandler.fetchClientMetadata(clientId);
+  if (!data)
+    throw createError({
+      statusCode: 400,
+      statusMessage: "Invalid or expired client ID.",
+    });
+
+  const token = await clientHandler.generateAuthToken(clientId);
+
+  return `drop://handshake/${clientId}/${token}`;
+});