⚡ Optimize timestamp generation in BackgroundService

[xRahul]

💡 What: Replaced moment().valueOf().toString() with Date.now().toString() in src/services/BackgroundService.js. Removed the unused moment import.

🎯 Why: Date.now() is a native V8 method and is significantly faster than creating a Moment object just to get the current timestamp. This reduces memory allocation and CPU usage.

📊 Measured Improvement:
Benchmark with 1,000,000 iterations:

• Moment.js: ~650ms
• Date.now(): ~73ms
• Improvement: ~9x faster

Added scripts/benchmark_moment.js to verify the performance gain.

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PR created automatically by Jules for task 11205205045823151434 started by @xRahul

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