feat: Reference schema support (#800) (#1307) #3027

Job	Run time
test_min_deps (windows-latest)	1m 21s
Integration Tests (pdm.lock)	36s
test_min_deps (macos-latest)	49s
test_min_deps (ubuntu-latest)	52s
Integration Tests (pdm.minimal.lock)	33s
test (3.9, ubuntu-latest)	1m 24s
test (3.10, ubuntu-latest)	1m 17s
test (3.9, macos-latest)	1m 11s
test (3.10, macos-latest)	1m 7s
test (3.11, ubuntu-latest)	1m 22s
test (3.12, ubuntu-latest)	1m 35s
test (3.12, macos-latest)	54s
test (3.12, windows-latest)	2m 2s
test (3.9, windows-latest)	2m 3s
test (3.11, macos-latest)	52s
test (3.11, windows-latest)	1m 40s
test (3.13, ubuntu-latest)	1m 34s
test (3.13, windows-latest)	2m 47s
test (3.13, macos-latest)	1m 8s
test (3.10, windows-latest)	2m 0s
Combine & check coverage	16s
	27m 23s

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