perf: skip schema creation and parse when validation is disabled

[chenjiahan]

Summary

When schema validation is disabled via RSPACK_CONFIG_VALIDATE=loose-silent, we can skip schema creation and parse to improve the performance.

Before (no difference with loose-silent):

After (20ms faster with loose-silent):

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).

[netlify]

✅ Deploy Preview for rspack canceled.

Name	Link
🔨 Latest commit	2cce224
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[codspeed-hq]

CodSpeed Performance Report

Merging #10768 will not alter performance

_{Comparing skip_schema_0624 (2cce224) with main (781e5b5)}

Summary

✅ 16 untouched benchmarks