fix: format max close size

[380712766-dot]

Summary

• Format the max close size before writing it into the close position input.
• Keep the input value aligned with the close order submission precision.
• Avoid browser number validation errors caused by floating point noise such as 9.1138999999.

Tests

• Ran git diff --check.

Note: I could not run the full npm build locally because npm is not installed in this environment.

Closes #11

[380712766-dot]

I opened a PR for this issue. Could you please assign this bounty to me?