fix(lint): remove unnecessary async keywords from synchronous functions

- Remove async from functions that don't use await
- Change return types from Promise<void> to void for synchronous functions
- Fixes all 8 require-await lint warnings
- Reduces total lint warnings from 63 to 55

ts/snmp/manager.ts

@@ -88,7 +88,7 @@ export class NupstSnmp {
    * @param retryCount Current retry count (unused in this implementation)
    * @returns Promise resolving to the SNMP response value
    */
-  public async snmpGet(
+  public snmpGet(
     oid: string,
     config = this.DEFAULT_CONFIG,
     retryCount = 0,