feat: simple delta and customized delta relationship #7951

Job	Run time
test	12m 44s
test-doc	1m 35s
cargo check MSRV (windows-2025)	3m 8s
Check MSRV badge	11s
WebAssembly (wasm32-wasip2)	1m 6s
test-fast (ubuntu-24.04-arm)	2m 48s
WebAssembly (wasm32-unknown-unknown)	51s
test-fixtures-windows (windows-11-arm)	16m 2s
test-fast (windows-11-arm)	12m 14s
test-32bit (arm32v7)	4m 36s
test-32bit-windows-size-doc	8m 19s
WebAssembly (wasm32-wasip1)	1m 2s
cargo-deny	29s
test-journey	3m 51s
pure-rust-build	2m 28s
test-fast (macos-latest)	2m 29s
check-blocking	7s
test-fast (ubuntu-latest)	2m 36s
cargo check MSRV (ubuntu-latest)	1m 37s
lint	4m 48s
cargo-deny-advisories	31s
test-fast (windows-latest)	8m 58s
test-32bit (i386)	6m 23s
check-no-persist-credentials	6s
test-fixtures-windows (windows-latest)	12m 44s
Tests pass	3s
	1h 51m 46s

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