Disable line numbers in code blocks

[Copilot]

Line numbers were rendering in a separate table column disconnected from the code content due to Kramdown's table-based layout with Rouge syntax highlighting.

Changes

• Disabled line_numbers for block code in _config.yml kramdown configuration
• Removed line_numbers_start setting (no longer applicable)

HTML Structure Change

Before:

<table class="rouge-table">
  <tr>
    <td class="rouge-gutter"><pre>1\n2\n3</pre></td>
    <td class="rouge-code"><pre>code here</pre></td>
  </tr>
</table>

After:

<pre class="highlight"><code>code here</code></pre>

Visual Impact

Before:

After:

Syntax highlighting and copy functionality remain unchanged.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Line Numbers for Code Blocks</issue_title>
<issue_description></issue_description>

Comments on the Issue (you are @copilot in this section)

@biggiebk Line numbers are being printed in the code first with no code and then the code is being printed. See the following URL.

https://biggiebk.github.io/theme_mymadlab/theme/introduction/2025/10/18/syntax-exmaples.html</comment_new>

• Fixes Line Numbers for Code Blocks #1

---

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[biggiebk]

I didn't want the line numbers removed. Wanted them to be displayed to the left of the code block.

[biggiebk]

They are currently being printed first with no code and the code is printed after the line numbers.

[biggiebk]

I did not ask that the line numbers be removed, but want the line numbers to be properly displayed on the left hand side of the code. Please open the following page for reference.

https://biggiebk.github.io/theme_mymadlab/theme/introduction/2025/10/18/syntax-exmaples.html