fix logging: include requested height in cert2 not found error

[imabdulbasit]

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[claude]

Claude finished @imabdulbasit's task in 54s —— View job

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Review of PR #4303

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LGTM — this is a clean, well-scoped improvement.

The change adds the requested_height to the not-found error message in get_leaf_proof_with_cert2, which will make debugging cert2 lookup failures much easier. A few observations:

• Consistent with existing patterns: Other error messages in this file already include dynamic context (e.g., "unknown header {requested}" on line 207, "missing epoch root header {epoch_root_height}" on line 434). This change follows the same convention.
• No performance concern: The format!() only runs in the error (None) path, so there's no cost on the happy path.
• No information leak risk: The block height is not sensitive — it's a public chain property already known to the caller.

No issues found. Ship it.

[gemini-code-assist]

Code Review

This pull request updates the error message in the light client API to include the requested height when a cert2 finality proof is not found, providing more context for the error. I have no feedback to provide as there were no review comments to evaluate.