Remove RegionBuilder and remaining references to region references #2439

Job	Run time
linux-gallery-python3.13-upgraded	1m 9s
linux-gallery-python3.9-minimum	52s
windows-gallery-python3.13-upgraded	2m 48s
windows-gallery-python3.9-minimum	1m 32s
linux-python3.13-ros3	1m 15s
linux-python3.13	2m 21s
linux-python3.13-upgraded	2m 17s
linux-python3.9-minimum	2m 4s
macos-python3.13-upgraded	1m 25s
macos-python3.9-minimum	3m 22s
windows-python3.13-upgraded	4m 21s
windows-python3.9-minimum	2m 59s
conda-linux-python3.13-upgraded	2m 16s
conda-linux-python3.9-minimum	2m 22s
Deploy pre-release from dev	0s
	31m 3s

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