feat(rpc): introduce FilterIter #6218

Job	Run time
Check no_std	2m 40s
Check WASM	3m 5s
Build & Test Examples (example_cli)	2m 39s
Build and test (stable, true, --no-default-features --features miniscript/no-std)	4m 49s
Build & Test Examples (example_bitcoind_rpc_polling)	30s
Rust fmt	13s
Build and test (stable, true, --all-features)	4m 7s
prepare	2s
Build & Test Examples (example_electrum)	1m 2s
Build and test (1.63.0, --no-default-features --features miniscript/no-std)	7m 44s
Build & Test Examples (example_esplora)	1m 4s
Build and test (1.63.0, --all-features)	6m 45s
Build & Test Examples (example_wallet_electrum)	1m 0s
Build & Test Examples (example_wallet_esplora_async)	1m 8s
Build & Test Examples (example_wallet_esplora_blocking)	56s
Build & Test Examples (example_wallet_rpc)	34s
clippy_check	2m 59s
	41m 17s

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