Create metrics endpoints for TMF Service related information

Create endpoints:

• GET /tmf-api/metrics/totalServices (optional params - state)
  • Exp. Resp: { totalServices: 32 }
• GET /tmf-api/metrics/servicesGroupByState (params - starttime: ISOdatetime and endtime:ISOdatetime e.g. 2025-04-14T11:08:10Z) - allow max 31 days diff / double check the TMF state names
  • Exp. Resp:

{ 
 services: {
   total: 8, 
   aggregations: {
     groupByState: {  
       [{ key:"RESERVED", count: 2 }, { key:"ACTIVE", count: 2 }, { key:"TERMINATED", count: 2 }, { key:"INACTIVE", count: 2 } ]
     }
   }
 }
}