🔒 Fix potential XSS via Unsanitized URL Attributes

[ffalcinelli]

🎯 What: Fixed a potential Cross-Site Scripting (XSS) vulnerability by sanitizing client.baseUrl, pageRedirectUri, and actionUri in error.ftl and info.ftl.
⚠️ Risk: A malicious javascript: or data: URI injected into the URL variables could execute unauthorized scripts when a user clicks the links.
🛡️ Solution: Implemented a robust blacklist validation !url?trim?lower_case?starts_with("javascript:") && !url?trim?lower_case?starts_with("data:") && !url?trim?lower_case?starts_with("vbscript:") before rendering the href attribute. This neutralizes malicious payloads while still allowing safe custom schemes (like myapp://callback) used by native mobile applications.

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PR created automatically by Jules for task 12205455578476273070 started by @ffalcinelli

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