starknet_patricia_storage: move is_gatherable to ReadOnlyStorage

[ArielElp]

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[ArielElp]

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• starknet_committer: fetch patricia paths concurrently #14283
• starknet_committer: define fetch_contract_storage_paths_concurrently #14282
• starknet_committer: define StoragePathsReadTask #14281
• starknet_patricia_storage: move is_gatherable to ReadOnlyStorage #14280 👈 (View in Graphite)
• apollo_committer,starknet_committer: use blockifier's AccessedKeys #14252
• apollo_committer: add new request handler #14003
• apollo_committer: add request_paths_and_commit_block tests #14208
• starknet_committer: delete patricia paths on reverts #14002
• starknet_committer,apollo_committer: add timers for fetch patricia paths #14189
• starknet_committer: underlying logic of the new read witnesses and commit endpoint #14001
• starknet_committer: extract metadata construction to a function #14000
• starknet_committer: extract commit plan to commit_or_load #13999
• starknet_committer: read and write patricia paths to index db #13998
• apollo_committer_types: add patricia proofs request and response types #13996 : 1 other dependent PR (#13997 )
• starknet_committer: add patricia paths forest reader/writer traits #13995
• starknet_committer: define StarknetForestProofs serde #13994
• starknet_committer: compute and store accessed keys digest #13993
• starknet_committer: add utility that returns sorted leaf indices #13992
• starknet_committer: abstract fetch_all_patricia_paths #13991
• starknet_patricia_storage: two layer storage #13990
• starknet_committer: move fetch_patricia_paths tests #13960
• starknet_committer: fetch patricia paths tests #13959
• starknet_committer: support both layouts in fetch_patricia_paths #13958
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PR Summary

Low Risk
Trait API relocation with mechanical impl updates; no change to gather semantics or persistence behavior.

Overview
Moves as_gatherable_storage from the Storage trait to ReadOnlyStorage, so callers can detect GatherableStorage support on read-only views without requiring write APIs.

Every backend and wrapper (Aerospike, Mdbx, RocksDB, Map, Cached, Null, ReadsCollector, TwoLayer, ShortKey) now implements the hook on its ReadOnlyStorage impl and drops the duplicate on Storage. Behavior is unchanged: gather-capable stores still return Some(self); wrappers that cannot gather return None.

CachedStorage’s ReadOnlyStorage impl bound is tightened to S: Storage + ImmutableReadOnlyStorage + 'static, matching its GatherableStorage / Storage impls.

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