Optimize regex compilation, React memoization, and memory management

[Copilot]

Identified and resolved performance bottlenecks causing inefficient CPU usage, excessive memory growth, and unnecessary React re-renders.

Server (server.js)

• Precompiled ANSI regex - Moved pattern to module scope with proper lastIndex reset to eliminate regex recreation overhead on every data event
• Conditional logging - Gated verbose console output behind NODE_ENV checks
• Connection limiting - Enforced MAX_CONNECTIONS (100) with graceful rejection to prevent resource exhaustion

Client (App.tsx)

• Memoization - Wrapped computed values (getButtonText, getButtonClass) in useMemo and event handlers (handleDisconnect, handleTerminalInput) in useCallback to prevent unnecessary re-renders
• Bounded message history - Capped array at 1000 messages, trimming to 900 to prevent unbounded growth
• Reduced string operations - Simplified message status checks from multiple conditionals to single else-if chain

Renderer (renderer.ts)

• MutationObserver - Set attributeOldValue: false to reduce memory overhead

Before:

function cleanAnsiSequences(text) {
    return text.replace(/\x1b\[[0-9;?]*[a-zA-Z]/g, '');  // Regex recreated every call
}

After:

const ansiRegex = /\x1b\[[0-9;?]*[a-zA-Z]/g;  // Compiled once
function cleanAnsiSequences(text) {
    ansiRegex.lastIndex = 0;
    return text.replace(ansiRegex, '');
}

Original prompt

Identify and suggest improvements to slow or inefficient code

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