refactor: Rename redisKeys.ts to chartStorageKeys.ts

Better name that reflects the purpose - composing keys for chart data storage,
not just Redis-specific utilities.

Author: pavelzotikov

src/services/chartDataService.ts

@@ -1,5 +1,5 @@
 import RedisHelper from '../redisHelper';
-import { composeTimeSeriesKey, getTimeSeriesSuffix } from '../utils/redisKeys';
+import { composeTimeSeriesKey, getTimeSeriesSuffix } from '../utils/chartStorageKeys';
 
 /**
  * Service for fetching chart data from Redis TimeSeries