Implement client heartbeats, improve display formatting, and fix UI

[chvvkumar]

📋 Overview

This pull request introduces a new client heartbeat mechanism with stale client pruning to enhance system monitoring and reliability. It also improves the readability of connection duration by formatting it in dd-hh-mm-ss. Additionally, the PR includes a fix for UI table column alignment for better consistency.

🔄 Changes by Category

• Features:
  • Implemented client heartbeat registration and stale client pruning within the SafetyMonitor in alpaca/device.py, with corresponding API and management route updates.
  • Formatted connection duration to dd-hh-mm-ss for improved readability in alpaca/routes/management.py and templates/setup.html.
• Bug Fixes:
  • Corrected table column text alignment to the right for better consistency in templates/setup.html.
• Tests:
  • Extensively updated and added new tests in tests/test_alpaca.py, particularly covering the new client heartbeat functionality and display formatting.

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_{📊 Analyzed 7 commit(s) | 🕐 Updated: 2026-01-05T04:19:22.840Z | Generated by GitHub Actions}

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