design blocks: symbols are never reannotated when placed as sheet

Description

When you place a design block as a sheet, the symbols in the block always keep the annotations from the library block, regardless of the state of the "keep annotations" setting. The expectation is the symbols in the block are reannotated if "keep annotations" is disabled, as they are when not placed in a sheet.

This is like #22620 (closed), except there the symbols are completely unannotated (R?) when placed as a group.

Steps to reproduce

1. Open demo project: v10-designblocks.zip
2. Open eeschema
3. enable "place as sheet" and disable "keep annotations" in design block panel
4. place "resistor" block
5. see that resistors in the subsheet are always R3 and R4, just as they are in the library, no matter how many times you place the block

KiCad Version

Application: KiCad Schematic Editor arm64 on arm64

Version: 9.99.0-4716-g5b12292b64, release build

Libraries:
	wxWidgets 3.2.8
	FreeType 2.13.3
	HarfBuzz 10.1.0
	FontConfig 2.15.0

Platform: macOS Sonoma Version 14.7.2 (Build 23H311), 64 bit, Little endian, wxMac
OpenGL: Apple, Apple M1, 2.1 Metal - 88.1

	wxWidgets: 3.2.8 (wchar_t,wx containers)
	Boost: 1.87.0
	OCC: 7.8.1
	Curl: 8.7.1
	ngspice: 45.2
	Compiler: Clang 16.0.0 with C++ ABI 1002
	KICAD_IPC_API=ON
	KICAD_USE_PCH=OFF