## Exercise 18: GPS Field QA

Survey/reconnaissance firmware for LilyGO T-Beam SUPREME.

This exercise measures GNSS visibility and solution quality, logs results to internal flash using CSV, and provides a minimal serial interface for retrieving the logs in the field.

Current storage choice:

- `SPIFFS`

Current environments:

- `bob_l76k`
- `guy_ublox`

Primary serial commands:

- `status`
- `summary`
- `ls`
- `cat <filename>`
- `stop`
- `erase_logs`

Notes:

- Samples are aggregated once per second.
- Records are flushed to flash every 10 seconds.
- Satellite snapshot records are written as additional CSV lines when GSV data is available.
- The implementation uses common NMEA parsing so it can normalize L76K and MAX-M10S output without adding a new GNSS dependency.
