🛡️ Sentinel: [HIGH] Fix weak random number generation for security purposes

[nilsreichardt]

🚨 Severity: HIGH
💡 Vulnerability: Weak random number generation (Random()) was used to generate seemingly secure strings, tokens, and IDs within the application across multiple internal utility functions (Id.generate, randomString, randomIDString, and AutoIdGenerator.autoId()). Standard random generation is predictable and should never be used for ID/token generation.
🎯 Impact: Using non-cryptographically secure random generators leaves generated IDs and tokens susceptible to brute force and prediction attacks, significantly reducing their reliability and safety.
🔧 Fix: Refactored instances of Random() to Random.secure() in id.dart, random_string.dart, and auto_id_generator.dart to enforce cryptographically secure pseudo-random number generation (CSPRNG) within these critical helper functions.
✅ Verification: Ran sz test and sz analyze successfully. Ensure that any newly generated values remain functionally identical but are structurally resistant to predictability.

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PR created automatically by Jules for task 216543709038818687 started by @nilsreichardt

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[gemini-code-assist]

Code Review

This pull request correctly addresses a critical security vulnerability by replacing the predictable Random() with the cryptographically secure Random.secure() for generating IDs and tokens. The changes are applied consistently across all relevant utility functions. I've added a couple of minor suggestions to improve code style and maintainability by using final instead of var for local variables, in line with the repository's style guide.

[gemini-code-assist]

For improved code clarity and to prevent accidental reassignments, it's best practice in Dart to use final for local variables that are not reassigned. This also aligns with the repository style guide's rule for consistency with var and final.

See style guide reference(s) below.

Suggested change

	var rand = Random.secure();
	final rand = Random.secure();

References

1. The style guide (line 101) recommends following a consistent rule for var and final on local variables. Using final for variables that are not reassigned is a strong convention that improves code safety and readability. ^(link)

[gemini-code-assist]

For improved code clarity and to prevent accidental reassignments, it's best practice in Dart to use final for local variables that are not reassigned. This also aligns with the repository style guide's rule for consistency with var and final.

See style guide reference(s) below.

Suggested change

	var rand = Random.secure();
	final rand = Random.secure();

References

1. The style guide (line 101) recommends following a consistent rule for var and final on local variables. Using final for variables that are not reassigned is a strong convention that improves code safety and readability. ^(link)

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