revert subtype theory + syntactic sugar for cloning it #3635

Job	Run time
EasyCrypt compilation (opam)	2m 43s
EasyCrypt compilation (nix)	1m 24s
Fetch EasyCrypt External Projects Matrix	3s
Check EasyCrypt Libraries (unit)	2m 54s
Check EasyCrypt External Projects (jasmin-eclib, https://github.com/jasmin-lang/jasmin, main, ecl...	3m 23s
Check EasyCrypt External Projects (sha3, https://gitlab.com/easycrypt/sha3, next, ., config/tests...	13m 51s
Check EasyCrypt Libraries (stdlib)	6m 31s
Check EasyCrypt External Projects (cryptobox, https://gitlab.com/fdupress/ec-cryptobox, next, ., ...	3m 51s
Check EasyCrypt Libraries (examples)	4m 27s
Check EasyCrypt External Projects (xsalsa20, https://gitlab.com/fdupress/ec-xsalsa, master, ., co...	3m 6s
Check EasyCrypt External Projects (xmss-acai, https://github.com/MM45/FV-XMSS-EC, master, ., conf...	8m 15s
Check EasyCrypt External Projects (xmss-fsai, https://github.com/MM45/FV-XMSS-EC, master, ., conf...	7m 43s
Check EasyCrypt External Projects (sphincsplus, https://github.com/MM45/FV-SPHINCSPLUS-EC, master...	20m 0s
Check EasyCrypt External Projects (set-status)	4s
Notification	0s
	1h 18m 15s

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