fix: Remove unnecessary <base> tag causing relative link routing issues

[wo-o29]

📝 Key Changes

Fixes #495 , #576

This PR removes the <base> tag injection from the transformHead function in shared.mts that was causing relative links to break in production builds.

Problem:
When clicking relative links like ./examples/submit-button.html from /code-quality/code/, the browser incorrectly navigates to /code-quality/examples/submit-button.html instead of the expected /code-quality/code/examples/submit-button.html.

Root Cause:
The HTML <base> tag forces all relative paths to resolve from /code-quality/, overriding the current page's path. This conflicts with VitePress's client-side routing, which already handles base path configuration correctly.

Solution:
Remove the manual <base> tag injection from transformHead. VitePress's built-in base configuration is sufficient for proper routing without the need for an explicit HTML <base> tag.

🖼️ Before and After Comparison

Before	After

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