Add support for Soroban external calls 🎉 #7057

Job	Run time
Repolinter	27s
Docs	1m 15s
Linux Arm	19m 45s
Container Image	11m 55s
Linux x86-64	36m 6s
Mac Arm	10m 47s
Mac Intel	1s
Stdlib	6s
Windows	8m 43s
Mac Universal Binary	0s
Anchor Integration test	0s
Polkadot Integration test	0s
Polkadot Integration test with subxt	0s
Solana Integration test	0s
Visual Code Extension	0s
Soroban Integration test	0s
Coverage report	0s
	1h 29m 5s

Provide feedback