feat(backend): add tRPC with Hono adapter

- Add @trpc/server, @hono/trpc-server, zod dependencies
- Create tRPC context with BetterAuth session
- Create router with publicProcedure and protectedProcedure
- Mount tRPC at /trpc/* via Hono adapter

Co-authored-by: Ona <no-reply@ona.com>

apps/aris-backend/src/trpc/context.ts

@@ -0,0 +1,14 @@
+import type { FetchCreateContextFnOptions } from "@trpc/server/adapters/fetch"
+
+import { auth } from "../auth/index.ts"
+
+export async function createContext(opts: FetchCreateContextFnOptions) {
+	const session = await auth.api.getSession({ headers: opts.req.headers })
+
+	return {
+		user: session?.user ?? null,
+		session: session?.session ?? null,
+	}
+}
+
+export type Context = Awaited<ReturnType<typeof createContext>>