PoV Reclaim Runtime Side (#3002)

# Runtime side for PoV Reclaim

## Implementation Overview
- Hostfunction to fetch the storage proof size has been added to the
PVF. It uses the size tracking recorder that was introduced in my
previous PR.
- Mechanisms to use the reclaim HostFunction have been introduced.
- 1. A SignedExtension that checks the node-reported proof size before
and after application of an extrinsic. Then it reclaims the difference.
- 2. A manual helper to make reclaiming easier when manual interaction
is required, for example in `on_idle` or other hooks.
- In order to utilize the manual reclaiming, I modified `WeightMeter` to
support the reduction of consumed weight, at least for storage proof
size.

## How to use
To enable the general functionality for a parachain:
1. Add the SignedExtension to your parachain runtime. 
2. Provide the HostFunction to the node
3. Enable proof recording during block import

## TODO
- [x] PRDoc

---------

Co-authored-by: Dmitry Markin <dmitry@markin.tech>
Co-authored-by: Davide Galassi <davxy@datawok.net>
Co-authored-by: Bastian Köcher <git@kchr.de>

cumulus/test/client/src/lib.rs

@@ -151,6 +151,7 @@ pub fn generate_extrinsic_with_pair(
 		frame_system::CheckNonce::<Runtime>::from(nonce),
 		frame_system::CheckWeight::<Runtime>::new(),
 		pallet_transaction_payment::ChargeTransactionPayment::<Runtime>::from(tip),
+		cumulus_primitives_storage_weight_reclaim::StorageWeightReclaim::<Runtime>::new(),
 	);
 
 	let function = function.into();
@@ -158,7 +159,7 @@ pub fn generate_extrinsic_with_pair(
 	let raw_payload = SignedPayload::from_raw(
 		function.clone(),
 		extra.clone(),
-		((), VERSION.spec_version, genesis_block, current_block_hash, (), (), ()),
+		((), VERSION.spec_version, genesis_block, current_block_hash, (), (), (), ()),
 	);
 	let signature = raw_payload.using_encoded(|e| origin.sign(e));
 
@@ -203,13 +204,16 @@ pub fn validate_block(
 	let mut ext_ext = ext.ext();
 
 	let heap_pages = HeapAllocStrategy::Static { extra_pages: 1024 };
-	let executor = WasmExecutor::<sp_io::SubstrateHostFunctions>::builder()
-		.with_execution_method(WasmExecutionMethod::default())
-		.with_max_runtime_instances(1)
-		.with_runtime_cache_size(2)
-		.with_onchain_heap_alloc_strategy(heap_pages)
-		.with_offchain_heap_alloc_strategy(heap_pages)
-		.build();
+	let executor = WasmExecutor::<(
+		sp_io::SubstrateHostFunctions,
+		cumulus_primitives_proof_size_hostfunction::storage_proof_size::HostFunctions,
+	)>::builder()
+	.with_execution_method(WasmExecutionMethod::default())
+	.with_max_runtime_instances(1)
+	.with_runtime_cache_size(2)
+	.with_onchain_heap_alloc_strategy(heap_pages)
+	.with_offchain_heap_alloc_strategy(heap_pages)
+	.build();
 
 	executor
 		.uncached_call(