feat: Make `Error` trait available in `no_std` mode #685

Job	Run time
Benchmark	43s
Check (x86_64-unknown-linux-gnu, 1.81.0)	12s
Check (x86_64-unknown-linux-gnu, stable)	6s
Clippy	15s
Check (x86_64-unknown-linux-gnu, nightly)	18s
Check (aarch64-apple-darwin, 1.81.0)	17s
Check (aarch64-apple-darwin, stable)	12s
Documentation	21s
Check (aarch64-apple-darwin, nightly)	20s
Check (x86_64-pc-windows-msvc, 1.81.0)	32s
Rustfmt	6s
Check (x86_64-pc-windows-msvc, stable)	45s
Check (x86_64-pc-windows-msvc, nightly)	28s
Test (x86_64-unknown-linux-gnu, 1.81.0)	27s
Test (x86_64-unknown-linux-gnu, stable)	23s
Test (x86_64-unknown-linux-gnu, nightly)	25s
Test (aarch64-apple-darwin, 1.81.0)	26s
Test (aarch64-apple-darwin, stable)	24s
Test (aarch64-apple-darwin, nightly)	34s
Test (x86_64-pc-windows-msvc, 1.81.0)	54s
Test (x86_64-pc-windows-msvc, stable)	52s
Test (x86_64-pc-windows-msvc, nightly)	59s
	9m 59s

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