Raising the area cap to 4600 put it above the largest area clamp/1 can
emit (45° lat × 100° lon = 4500 sq deg), so :viewport_too_large became
unreachable and the 413 handlers in both cell controllers became dead
code.
Remove the cap, the error branch, the max_viewport_area_sq_deg/0
accessor and both payload_too_large/1 handlers. The clamp is what
bounds request cost: post-clamp nothing can ask for more than the full
grid (~92k cells, ~1.4 MB), which is materialized once per valid_time
and served from cache, so a global viewport costs no more than a fully
zoomed-out map.
Replaces the cap test with one asserting the clamp never lets absurd
input escape the supported extent — the property the guard was
standing in for.
Graham McIntire
7c37bf67fe