starknet_patricia: derive Serialize and Deserialize for SubTreeHeight

[itamar-starkware]

No description provided.

[itamar-starkware]

• apollo_storage: add state_commitment_infos table #14448
• starknet_committer,starknet_os: relocate commitment infos to starknet_committer #14447
• starknet_patricia: derive Serialize and Deserialize for SubTreeHeight #14446 👈 (View in Graphite)
• main

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[reviewable-StarkWare]

This change is 

[itamar-starkware]

Why this PR exists

Foundation of a 3-PR stack (#14446 → #14447 → #14448) whose goal is to persist the OS-input commitment data (StateCommitmentInfos) in apollo_storage.

Storing that type means (de)serializing it through serde. StateCommitmentInfos contains CommitmentInfo, which has a tree_height: SubTreeHeight field — and SubTreeHeight today derives only a feature-gated Deserialize and no Serialize at all. So the structs that embed it can't be serialized for storage.

This PR makes SubTreeHeight derive Serialize + Deserialize unconditionally (matching how HashOutput already does it), so the types that contain it become storable. No behavior change beyond the added trait impls — it just unblocks #14447 / #14448.

[yoavGrs]

@yoavGrs reviewed 2 files and all commit messages, and resolved 1 discussion.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on itamar-starkware).