feat(api): register boardRouter in OpenAPI router

Expose board endpoints in the Scalar API documentation.

packages/api/src/open-api.ts

@@ -3,6 +3,7 @@ import { generateOpenApiDocument } from "trpc-to-openapi";
 import { API_KEY_HEADER_NAME } from "@homarr/auth/api-key";
 
 import { appRouter } from "./router/app";
+import { boardRouter } from "./router/board";
 import { infoRouter } from "./router/info";
 import { inviteRouter } from "./router/invite";
 import { userRouter } from "./router/user";
@@ -10,6 +11,7 @@ import { createTRPCRouter } from "./trpc";
 
 export const openApiRouter = createTRPCRouter({
   appRouter,
+  boardRouter,
   infoRouter,
   inviteRouter,
   userRouter,