Implement Comprehensive Monitoring and Observability

## Overview
Set up complete monitoring stack with Prometheus, Grafana, and distributed tracing for production observability.

## Business Value
Comprehensive monitoring is essential for production operations, debugging, and performance optimization.

## Current State
- Basic health checks exist
- No metrics collection
- No distributed tracing
- No dashboards

## Subtasks
- [ ] Set up Prometheus
- [ ] Add metrics instrumentation
- [ ] Configure Grafana dashboards
- [ ] Implement distributed tracing
- [ ] Add log aggregation
- [ ] Create alerting rules
- [ ] Document monitoring

## Implementation Steps
1. Set up Prometheus
2. Add metrics to code
3. Configure Grafana
4. Add tracing
5. Set up alerts

## Acceptance Criteria
- [ ] Metrics are collected
- [ ] Dashboards are available
- [ ] Tracing works
- [ ] Alerts are configured
- [ ] Documentation exists

## Estimated Effort
- Hours: 24-32
- Complexity: Medium

Start by locating the existing health checks and production configuration, then inventory the telemetry and dashboard requirements in this issue. Define the Prometheus, Grafana, tracing, logging, and alerting integration points before implementing them. Done means metrics, dashboards, tracing, alerts, and monitoring documentation are present and verified.

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