perf(backend): cache timeline of a channel to redis

packages/backend/src/misc/id/aid.ts

@@ -23,3 +23,8 @@ export function genAid(date: Date): string {
 	counter++;
 	return getTime(t) + getNoise();
 }
+
+export function parseAid(id: string): { date: Date; } {
+	const time = parseInt(id.slice(0, 8), 36) + TIME2000;
+	return { date: new Date(time) };
+}