Fix three-level nested list indentation

[Copilot]

This PR fixes an issue where three-level nested lists were not being indented correctly. Level 3 items were appearing at the same indentation as Level 2 items instead of being properly nested.

Problem

The following HTML:

<ul>
    <li><a>Level 1</a>
        <ul>
            <li><a>Level 2</a></li>
            <li><a>Level 2</a></li>
            <li><a>Level 2</a>
                <ul>
                    <li><a>Level 3</a></li>
                    <li><a>Level 3</a></li>
                </ul>
            </li>
        </ul>
    </li>
</ul>

Was converted to:

*   [Level 1](A/Lorem.htm)

    *   [Level 2](A/Lorem.htm)
    *   [Level 2](A/Lorem.htm)
    *   [Level 2](A/Lorem.htm)

    *   [Level 3](A/Lorem.htm)  <!-- Should be indented more -->
    *   [Level 3](A/Lorem.htm)  <!-- Should be indented more -->

Solution

Fixed two issues in the list processing logic:

1. Regex pattern fix: Changed \n([ ]*)+(\*|\d+\.) to \n([ ]*)(\*|\d+\.)

   • The original ([ ]*)+ pattern was capturing empty strings instead of actual spaces due to regex group behavior
   • The fixed pattern properly captures indentation spaces for calculation

2. Removed conflicting indentation: Modified TwoNewLines() replacement to avoid double-indentation

   • Removed extra 4-space indentation that was conflicting with NestedList() indentation logic
   • Let NestedList() handle all indentation consistently

Result

Now produces correctly indented output:

*   [Level 1](A/Lorem.htm)

    *   [Level 2](A/Lorem.htm)
    *   [Level 2](A/Lorem.htm)
    *   [Level 2](A/Lorem.htm)

        *   [Level 3](A/Lorem.htm)  <!-- Correctly indented with 8 spaces -->
        *   [Level 3](A/Lorem.htm)  <!-- Correctly indented with 8 spaces -->

• ✅ Level 1 lists: 0 spaces
• ✅ Level 2 lists: 4 spaces
• ✅ Level 3 lists: 8 spaces (was 4 before)

All existing tests continue to pass, ensuring backward compatibility.

Fixes #110.

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[baynezy]

This needs to be rebased

[Copilot]

This needs to be rebased

Rebased against develop branch in commit 4d70621. Also fixed test failures by trimming trailing whitespace in list items to prevent extra blank lines.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud