Add Agent Capacity Planner - interactive fleet capacity planning tool

Interactive capacity planning page with:
- Workload configurator (agents, messages/min, tokens, peak multiplier, model tier)
- Live Canvas chart showing 24h load simulation with animated data
- Real-time metrics (utilization, cost, throughput, queue depth, dropped requests)
- Bottleneck detector with severity levels and fix suggestions
- Auto-scaling simulation overlay on the load chart
- What-If scenarios (Normal, Product Launch 10x, DDoS 100x, Growth +20%/mo)
- Scenario comparison table
- Optimization recommendations with one-click apply
- JSON export and shareable URL with config encoded in hash
- Toggles for caching, request batching, and priority queuing

Usage: Open capacity-planner.html, adjust sliders to model your workload,
review bottlenecks and recommendations, try different scenarios.

Author: sauravbhattacharya001