🛡️ Sentinel: Add Trusted Types to CSP to block DOM XSS

[keough99]

🚨 Severity: MEDIUM
💡 Vulnerability: The application was missing strict Content-Security-Policy (CSP) directives to prevent DOM-based Cross-Site Scripting (XSS).
🎯 Impact: An attacker could potentially find a way to execute malicious scripts via unsanitized DOM sinks, leading to account compromise or unauthorized actions.
🔧 Fix: Added require-trusted-types-for 'script'; trusted-types 'none'; to the CSP meta tag to strictly enforce Trusted Types and block DOM-based XSS attacks globally.
✅ Verification: Ensured the new CSP directives were added properly and tests continue to pass without functionality breakage.

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PR created automatically by Jules for task 7074669104340125073 started by @keough99

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