pcb-scene3d-viewer 1.3.1

Version 1.3.1 renders source-classified via solder mask as a surface treatment
without replacing the plated copper barrel material.

Via rendering

Gerber vias with either isTentingTop or isTentingBottom use the covered
via rendering path; both fields explicitly false retain the exposed path.
Each tented board surface receives its own solder-mask ring above the copper
annulus. Mixed top/bottom tenting is preserved.
The mask ring keeps the authored drill opening clear and leaves the plated
through-hole wall copper-colored.
Blind and buried surface reachability remains authoritative, so mask geometry
is added only where a via actually reaches the corresponding board surface.

Existing CircuitJSON default-tenting and explicit-opening behavior is
unchanged.
Scene, controller, runtime, export, and package entrypoints are unchanged.
Tests cover fully tented, mixed, and fully open Gerber classification plus
copper-barrel and one-sided mask-ring material routing.