feat: ✨ finish File System pallet benchmarking

[TDemeco]

This PR completes the benchmarking of the File System pallet.

• Client changelog:
  • Added two RPC methods to the client (generateFileKeyProofBspConfirm and generateFileKeyProofMspAccept) which generate the file key proof needed by BSPs or MSPs to confirm or accept a storage request, using the special chunk challenges given by the runtime.
  • Added a check to the BSP submit proof task when reacting to the ProcessSubmitProofRequest event, to avoid submitting proofs if there're no challenges to respond to.
    • This should not happen in a real-world scenario since there should always be random challenges, but it was panicking when building with the runtime-benchmarks feature flag since that scenario does not have them, so I though might as well add a check there since it doesn't hurt and gives us a bit more flexibility with random challenges in the future.
• Runtime changelog:
  • Modified the bsp_confirm_storing extrinsic of the File System pallet to use the already-existing struct FileKeyWithProof instead of a tuple of the file key and proof to make it tidier. Modified all interactions with bsp_confirm_storing to accomodate for this change.
  • Added missing calls to decrease_capacity_used for MSPs in both the delete_file and pending_file_deletion_request_submit_proof extrinsics of the File System pallet. Previously, used capacity of the MSP that held the deleted file wasn't being updated when it should after verifying the inclusion proof.
  • Created the benchmark_proofs_template.rs template file, which is used by the script that generates the proofs required to benchmark the File System pallet.
  • Incremented the StorageRequestTtl when compiling with the runtime-benchmarks feature flag to 2000 to avoid storage requests expiring when generating the required file key proofs in the aforementioned script.
  • Benchmarked the File System pallet completely, considering the input variables for each extrinsic and the worst-case scenario when checking for divergent paths in the weight calculation phase would be too costly. Details of each benchmark can be found in the corresponding benchmarking.rs file.
• Scripts and integration tests changelog:
  • Developed the script to generate the required inclusion and non-inclusion forest proofs, file keys and file key proofs, bucket IDs and bucket roots for all required benchmark cases of the File System pallet.
  • Updated the newBucket method of the integration testing API to be able to receive the MSP ID that should store the new bucket.

[snowmead]

beast

[ffarall]

Suggested change

	// Since the BSP only requires one non-inclusion proof and 1 to 10 (MaxBatchBspConfirmStoring) file key proofs, we reutilise the
	// Since the BSP only requires one non-inclusion proof and 1 to 10 (MaxBatchBspConfirmStoring) file key proofs, we reuse the

[ffarall]

I assume this means you'll set the BSP's root to be the root of the bucket, right?

[TDemeco]

Yep!