Improve test readability by making decimal place adjustments explicit

[lumoswiz]

Currently test cases accommodate decimal place adjustments implicitly in their assertions. Look to refactor this to make decimal adjustments more explicit.

Proposed improvement:

• Express initial values explicitly with decimal places.
• Make assertions that clearly show the decimal adjustment: assertEq(value * 10 ** (18 - D), otherValue);

This change will make the test logic more transparent and easier to maintain.

Reference: Discussion in PR #36