DRC_ERROR doesn't work in PCB text

Description

I wanted to use ${DRC_ERROR} in a placeholder text in a template to force the user to fill in the missing text, but this does not trigger a DRC error. ${} substitutions are definitely being evaluated during DRC since I was able to workaround this by using a fake variable name to trigger a substitution error instead, so I would absolutely expect DRC_ERROR and DRC_WARNING to operate in this context.

Steps to reproduce

1. Create a text object on the PCB on any layer containing ${DRC_ERROR test}
2. Run DRC

KiCad Version

Application: KiCad arm64 on arm64

Version: 9.0.9, release build

Libraries:
	wxWidgets 3.2.8
	FreeType 2.14.3
	HarfBuzz 12.3.2
	FontConfig 2.17.1
	libcurl/8.7.1 (SecureTransport) LibreSSL/3.3.6 zlib/1.2.12 nghttp2/1.64.0

Platform: macOS Sequoia Version 15.7.7 (Build 24G720), 64 bit, Little endian, wxMac

Build Info:
	Date: Apr 29 2026 22:35:13
	wxWidgets: 3.2.8 (wchar_t,wx containers)
	Boost: 1.90.0
	OCC: 7.9.3
	Curl: 8.7.1
	ngspice: 44.2
	Compiler: Clang 17.0.0 with C++ ABI 1002
	KICAD_IPC_API=ON