Freeze the colocation periods and the hourly averaging rule

Freeze the colocation periods and the hourly averaging rule

Record the sensor identifiers, the reference monitor, the calibration period, the blind period that follows it, and how sub-hourly readings become an hourly value. Define the minimum sample count for a valid hour. Deliverable: A period manifest with start and end timestamps, the averaging rule, and a count of valid and invalid hours per sensor.