revert subtype theory + syntactic sugar for cloning it #3648

Job	Run time
EasyCrypt compilation (opam)	2m 43s
EasyCrypt compilation (nix)	1m 14s
Fetch EasyCrypt External Projects Matrix	3s
Check EasyCrypt Libraries (unit)	2m 47s
Check EasyCrypt External Projects (jasmin-eclib, https://github.com/jasmin-lang/jasmin, main, ecl...	3m 23s
Check EasyCrypt Libraries (stdlib)	6m 41s
Check EasyCrypt External Projects (sha3, https://gitlab.com/easycrypt/sha3, next, ., config/tests...	14m 9s
Check EasyCrypt Libraries (examples)	4m 27s
Check EasyCrypt External Projects (cryptobox, https://gitlab.com/fdupress/ec-cryptobox, next, ., ...	3m 44s
Check EasyCrypt External Projects (xsalsa20, https://gitlab.com/fdupress/ec-xsalsa, ec-main, ., c...	3m 14s
Check EasyCrypt External Projects (xmss-acai, https://github.com/MM45/FV-XMSS-EC, master, ., conf...	8m 37s
Check EasyCrypt External Projects (xmss-fsai, https://github.com/MM45/FV-XMSS-EC, master, ., conf...	7m 36s
Check EasyCrypt External Projects (sphincsplus, https://github.com/MM45/FV-SPHINCSPLUS-EC, master...	20m 33s
Check EasyCrypt External Projects (set-status)	1s
Notification	5s
	1h 19m 17s

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