Ports the data model of the board Item hierarchy (Item base, Pin,
ObstacleArea/ConductionArea, Via, Trace) and BasicBoard (layers, nets,
clearance, bounding box, items with query helpers), then build_board:
the load-bearing integration that constructs a BasicBoard from a parsed
DsnBoard.
build_board maps layers -> LayerStructure, resolution -> transform,
default clearance rule -> ClearanceMatrix, nets -> Nets plus a
(component,pin)->net map, padstacks x placement -> Pin items, and
keepouts -> ObstacleArea items. Rectangle pads become exact IntBoxes,
convex polygon pads exact Simplexes, circle pads their bounding box
(documented approximation); every pad is centred on its pin location so
it contains that location by construction. Trace/Via are router-produced
and lightweight here (an imported unrouted board has none).
Validated on a real KiCad export (kicad_routable.dsn): layer/net/pin
counts match the parsed DSN, every pin's pad shape contains its origin,
every pin reports a valid net, and pin locations lie in the board
bounding box. An oracle-gated test cross-checks that every net the
reference FreeRouting JAR routes exists on the constructed board.
Ryan Malloy
4220fe0cd6