IMG-020: Weak Data URI Validation

[murdore]

Summary

Data URI validation only checks for 'data:' prefix and 'base64,' delimiter.

Root Cause

Lines 420-426 minimal validation without MIME type or base64 content validation.

Fix

Use strict regex and validate base64 content.

Acceptance Criteria

• [ ] Implement strict data URI regex validation
• [ ] Validate MIME type format (type/subtype)
• [ ] Validate base64 content
• [ ] Add tests for valid and invalid data URIs