🔒 Fix Insecure Randomness for Cryptographic Salt in App.tsx

[jason420247]

🎯 What: Replaced insecure Math.random() usage in TrinityKeystore.getVector with Web Crypto API (crypto.getRandomValues) to provide cryptographically secure, unpredictable random salts.

⚠️ Risk: If left unfixed, attackers or third parties can predict generated salt vectors since Math.random() uses an insecure pseudorandom number generator (PRNG) with predictable seeds/sequences, undermining security and compromising the cryptographic vectors. Direct window referencing could also throw ReferenceError during Node.js/SSR execution.

🛡️ Solution:

1. Leveraged a high-entropy Uint32Array with crypto.getRandomValues() to generate safe salt values (CSPRNG).
2. Resolved the Web Crypto API dynamically (checking both window.crypto and globalThis.crypto) to avoid SSR/ReferenceError runtime issues.
3. Added robust JSDoc security documentation clarifying the architecture and preventing regressions.

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PR created automatically by Jules for task 5502306800814260100 started by @jason420247

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