Capacitor Healthkit fixes

[mpgxvii]

• Store only poll times/offsets in cache rather than the complete healthkit data (since this is in the phone already)
• This prevents storing and fetching of large amounts of data from storage (since we can pull this directly from HealthKit)
• Currently supported datatypes:

export enum HealthkitDataType {
  STEP_COUNT = 'stepCount',
  FLIGHTS_CLIMBED = 'flightsClimbed',
  DISTANCE_WALKING_RUNNING = 'distanceWalkingRunning',
  DISTANCE_CYCLING = 'distanceCycling',
  ACTIVE_ENERGY_BURNED = 'activeEnergyBurned',
  BASAL_ENERGY_BURNED = 'basalEnergyBurned',
  HEART_RATE = 'heartRate',
  APPLE_EXERCISE_TIME = 'appleExerciseTime',
  BLOOD_GLUCOSE = 'bloodGlucose',
  SLEEP_ANALYSIS = 'sleepAnalysis',
  WEIGHT = 'weight',
  WORKOUT_TYPE = 'workoutType'
}

• Also refactors sending of data to kafka: now converts to kafka object and sends for every object that gets converted, rather than waiting for all kafka objects to complete conversion/processing