paint_cell_at, erase_cell_at, cycle_rotation, save plus thin
wrappers for the UI hit-tests (set_active_layer/_atlas/_tile,
toggle_layer_visible/_roof_mode/_picker). Each action updates
state and delegates the actual map mutation to lib-core.maps.
Singleton table covering map id+path, active layer/atlas/tile/rot,
roof-mode flag, per-layer visibility flags, dirty flag, and picker
open/close state. Mutations go through setters so the test module
can verify state transitions without poking the internal table.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Empty launchable module with deps on lib-core.maps 0.4.0, render,
camera, input, and the fa_terrain_v1 asset alias. Renders the
default 4x4 empty work-map; interactive editing wired in
subsequent commits.
