fix: correct insertion sort loop structure

[trett1004]

Summary

This PR fixes the insertion sort implementation by removing a redundant outer loop that repeated the full insertion process unnecessarily.

Problem

The previous implementation wrapped the normal insertion pass inside an unnecessary extra full loop.
That caused repeated work without improving correctness.

Complexity Impact

• Expected insertion sort complexity: O(n²) (average/worst case)
• Previous implementation complexity: effectively O(n³) due to the extra outer loop
• Updated implementation restores expected O(n²) behavior

What changed

• Removed the unnecessary outer loop in insertion sort
• Kept the existing visualization behavior and state updates intact

Related Issue

N/A

UI Changes

N/A (no UI layout changes)