Refactor Soroban decoding/encoding logic #7126

Job	Run time
Docs	1m 19s
Linux x86-64	43m 8s
Container Image	12m 10s
Linux Arm	19m 9s
Mac Arm	10m 40s
Mac Intel	16m 9s
Repolinter	1m 11s
Stdlib	2m 4s
Windows	27m 56s
Mac Universal Binary	22s
Anchor Integration test	6m 52s
Solana Integration test	3m 26s
Polkadot Integration test with subxt	4m 37s
Polkadot Integration test	2m 50s
Soroban Integration test	12m 30s
Visual Code Extension	2m 35s
Coverage report	0s
	2h 46m 58s

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