feat!: `used_extensions` calls for both ops and signatures #2849

Job	Run time
Check for changes in Python files	5s
Build HUGR binary	1m 0s
check python 3.10	10s
Check serialization schema	7s
check python 3.13	22s
test python 3.10	21s
test python 3.13	39s
Required checks 🐍	1s
	2m 45s

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