feat(auto): Omni-Contributor Swarm God-Tier fixes for Security, Performance, and Architecture

[subbareddypalagiri]

Overview

This pull request is automatically generated by the Antigravity God-Tier Omni-Contributor Swarm.

Changes Made

• Security: Added NullPointerException and timing attack mitigations in MockAuthenticator.java.
• Performance: Replaced ThreadLocal with Netty's FastThreadLocal in StringUtil.java to prevent event loop leaks.
• Architecture: Applied DRY principles in FutureUtil.java by refactoring CompletableFuture exception handling.

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Authored by Antigravity God-Tier Swarm.

[lhotari]

This pull request is automatically generated by the Antigravity God-Tier Omni-Contributor Swarm.

Authored by Antigravity God-Tier Swarm.

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