Via placer: can't place vias on top of copper graphics with nets

Description

The via placer (standalone, not the router) does not accept placements inside copper graphics, saying "via location violates DRC".

Steps to reproduce

1. Add a graphic shape (e.g. a filled rectangle) on a copper layer and assign it a net (such as by placing it over a pad)
2. Try to place a via on the shape

KiCad Version

Application: KiCad PCB Editor arm64 on arm64

Version: 9.0.4, release build

Libraries:
	wxWidgets 3.2.8
	FreeType 2.13.3
	HarfBuzz 10.1.0
	FontConfig 2.15.0

Platform: macOS Sonoma Version 14.4.1 (Build 23E224), 64 bit, Little endian, wxMac
OpenGL: Apple, Apple M1 Pro, 2.1 Metal - 88

	wxWidgets: 3.2.8 (wchar_t,wx containers)
	Boost: 1.87.0
	OCC: 7.8.1
	Curl: 8.7.1
	ngspice: 44.2
	Compiler: Clang 16.0.0 with C++ ABI 1002
	KICAD_IPC_API=ON