[Feature Request] User defined schedules

### Is your feature request related to a problem? Please describe.

Inspections commonly include particular regions (e.g. grid cells in bathymetry, piles, etc), which may determine the types of data processing and analysis which need to occur. While naive data alignment by timestamp is definitely useful, more meaningful alignment is more likely based on user-defined regions, which may be defined by location data or time periods.

### Describe the solution you'd like

- [ ] allow users to define regions with IDs
- [ ] support regions having a parent
- [ ] support properties/tags for regions (allows different types of analysis in different region types)
- [ ] support area polygons/central positions for regions (allows intelligent querying, and some level of plotting)
- [ ] support user-defined schedules that map time periods to region IDs (query timestamp -> most specific region ID)
- [ ] support location querying (query location -> most specific region ID)

### Describe alternatives you've considered

| alternative | reason(s) why unsuitable |
|---|---|
| no regions, just timestamps | limits utility of alignment and analysis |

### Additional context

- known regions could allow rough geo-tagging of photos even without a positioning system on the vehicle
- regions with locations and/or area polygons can be plotted, which can help make sense of data