[TRIVIAL] handle input value too low error

[MartinquaXD]

Description

OKX returns error code 51006 for tiny orders or where the API can't figure out the price for the given token.
This recently created alert noise for orders selling the ICP token.

Changes

explicitly handle error code 51006

[claude]

Claude finished @MartinquaXD's task in 29s —— View job

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PR Review

• Read PR diff and surrounding code
• Verify error-code mapping and downstream handling
• Post review

Verdict: LGTM ✅

The change adds OKX error code 51006 ("Input value is too low") to the set mapped to Error::NotFound in handle_api_error. This is the correct classification — okx::Error::NotFound is treated as a benign "no swap available" outcome (crates/solvers/src/infra/dex/mod.rs:104), same as the existing 51005/82000/82104/82112 codes, so it will suppress the alert noise described in the PR rather than surfacing as an API error.

Consistent with existing style (documented inline comment, groups with the other not-found codes). No issues found.

Minor (non-blocking) nit not worth a change: 51006 sits after the 82xxx codes rather than next to its sibling 51005, but the list isn't strictly numerically ordered anyway.
· okx-handle-input-value-too-low