🔒 Fix Insecure Randomness for Cryptographic Salt in App.tsx

[jason420247]

🎯 What: Replaced the use of Math.random() with the cryptographically secure crypto.getRandomValues() Web Crypto API within TrinityKeystore.getVector in App.tsx. Added a cross-environment Web Crypto API resolver checking both window and globalThis.

⚠️ Risk: Math.random() produces predictable values, which are unsuitable for cryptographic contexts or securing salts. If left unfixed, an attacker could predict generated keystore vector salts and potentially compromise cryptographic elements or authentication vectors.

🛡️ Solution: Implemented crypto.getRandomValues() on a Uint32Array buffer, resolving the crypto instance safely across client/server boundaries (detecting window vs. globalThis) to prevent runtime environment reference errors.

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PR created automatically by Jules for task 14429529345203122852 started by @jason420247

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