R.maps.objects was f.opt(f.list(f.any)): a static wild encounter's
species (OverworldController.lua's d.pokemon, handed straight to
BattleState.newWild) went completely unchecked at load time, unlike an
encounter slot's species. A typo'd or removed id sat in a loaded mod
and only surfaced as a crash the moment a player reached that object.
Objects share one array across every kind -- NPCs, signs, warps and
static encounters all coexist with no field the loader could use to
tell them apart ahead of time -- so a strict f.rec covering the whole
shape would reject every kind this schema does not enumerate. Added
f.partial, an open counterpart to f.rec: it type-checks (and, through
collectRefs, cross-reference-checks) only the fields it is given and
leaves everything else on the value alone, the same extensibility
f.rec already grants at a record's top level but nowhere further in.
R.maps.objects now types just `pokemon` through it, so a bad species
id is a load-time "unresolved reference" error instead of a runtime
crash, while an NPC object's sprite/movement/range/... fields -- never
named in this schema -- still pass through untouched.