🛡️ Sentinel: [HIGH] Fix path traversal in verification document retrieval

[Pmaster-dev]

🚨 Severity: HIGH
💡 Vulnerability: Path traversal vulnerability in GET /api/v1/verification/:id/document where arbitrary file paths could be read using res.sendFile(verification.data.path, { root: '/' }).
🎯 Impact: Unauthorized reading of arbitrary system files on the host filesystem if document path data is manipulated.
🔧 Fix: Added path resolution and strict containment checks verifying verification.data.path resides inside the target uploads directory before sending the file.
✅ Verification: Unit test added in server/api/v1/verification.test.ts to confirm path traversal payloads are rejected; full vitest test suite executed and passed.

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PR created automatically by Jules for task 10077259530791301284 started by @Pmaster-dev

[google-labs-jules]

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