🛡️ Sentinel: [MEDIUM] Fix weak random number generation for security context

[thirdeyenation]

🚨 Severity: MEDIUM (Weak random number generation for security purposes)

💡 Vulnerability: The application was using the standard, cryptographically weak random module (random.choices) to generate security-sensitive data. Specifically, it was generating the 32-character root SSH password (in prepare.py) and various short IDs (in agent.py and helpers/guids.py).

🎯 Impact: random.choices generates pseudorandom numbers that are predictable if the internal state of the generator is known or can be guessed. This could theoretically allow an attacker to predict generated IDs or even brute-force/guess the generated root password, compromising the application or host environment.

🔧 Fix: Replaced occurrences of random.choices with secrets.choice using a generator expression. The secrets module is designed specifically for generating cryptographically strong random numbers suitable for managing data such as passwords, account authentication, security tokens, and related secrets.

✅ Verification:

• Ensured all instances of random.choices were completely removed from the codebase.
• Ran tests to ensure the new secrets.choice generator implementation generates the correctly sized strings and works without issue.

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PR created automatically by Jules for task 2489852159861749205 started by @thirdeyenation

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