🛡️ Sentinel: [HIGH] Fix Path Traversal in LeaseFileLockingService

[tomdesair]

🚨 Severity: HIGH
💡 Vulnerability: A Path Traversal vulnerability was identified in LeaseFileLockingService and LeaseFileMutex. These classes resolved UploadId directly against the storagePath to generate .lock, .stop, and .mutex files, which means an attacker could provide a malicious UploadId containing traversal characters (like ../../../) to access or modify files outside the intended storage directory.
🎯 Impact: This could allow attackers to manipulate or corrupt arbitrary files on the server (like ../../../tmp/malicious.lock), potentially leading to unauthorized access, denial of service, or further exploitation.
🔧 Fix: Implemented validation checks in getLockDirPath, getStopFilePath (in LeaseFileLockingService), and the constructor of LeaseFileMutex. The fix uses path.normalize().toAbsolutePath().startsWith(storagePath.normalize().toAbsolutePath()) to strictly verify that the generated paths are bounded within the designated storagePath.
✅ Verification: Ensure the unit tests pass (mvn test). Also ran mvn checkstyle:check and format tools.

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PR created automatically by Jules for task 11616360575913462100 started by @tomdesair

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[coveralls]

coverage: 94.834% (-0.05%) from 94.885% — bugfix/sentinel-path-traversal-leasefile-11616360575913462100 into master