fix: reject --oid values above 2^53-1 on perp cancel

[crazywriter1]

Summary

• perp cancel --oid parsed via parseInt which silently rounds uint64 IDs above 2^53-1, potentially cancelling the wrong order
• Add Number.isSafeInteger guard — same logic the response path already uses to withhold unsafe oids from output
• Add regression tests: unsafe oid rejected, MAX_SAFE_INTEGER accepted

Test plan

• npx vitest run src/__tests__/perp.test.js -t cancel
• --oid 9007199254740992 (2^53) → error: "exceeds safe integer precision"
• --oid 9007199254740991 (2^53-1) → passes validation

[nansen-pr-reviewer]

pr-reviewer Summary for #223a9d5

✅ No issues found

The code review completed successfully with no findings.

Review effort: 1/5 (Trivial)

Summary

This PR correctly fixes a real trading-safety bug: parseInt on a uint64 order ID above 2^53-1 silently produces the wrong value, which could cancel the wrong order. The Number.isSafeInteger guard is the right tool here, is consistent with how the response path already handles unsafe oids, and is placed at exactly the right point in the call chain — before the value reaches buildCancelAction. The regression tests are well-structured and cover both the rejection boundary and the acceptance boundary. The changeset is present, correctly typed as patch, and targets the right package. src/schema.json requires no update since the --oid option already exists and its type/description haven't changed. No findings.

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Token usage: 828 input, 2,151 output, 163,103 cache read, 17,597 cache write | Usage Guide

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[nansen-pr-reviewer]

Auto-approved

This PR was automatically approved because:

• Claude recommends approval
• Claude assessed this as a minimal effort change
• The effort level is within the auto-approval threshold of 2
• No high or critical issues were detected

If you have any concerns, please request a manual review.

[crazywriter1]

Friendly ping. This is ready for review when you have a moment. Happy to address any feedback. @kome12