Feat/required request fields

[moonlander101]

Addresses #508 at voiden

Alongside core changes

Changes:

• Extracts required-field metadata from REST request tables.
• Passes that metadata to the core request-processing pipeline.
• Preserves separate handling for cookies and HTTP headers.
• Removes the plugin’s duplicate static table headers because the core editor now renders them.
• Preserves upstream block-help and description-column behavior.
• Validation: the production plugin build passed with 138 modules transformed.
• Companion PR to the core Voiden change; both are needed for the complete feature.