feat: implement Prometheus monitoring, Grafana dashboards, and Telegram alerting

[memreo]

Summary

This PR implements the complete Prometheus & Grafana monitoring and Telegram alerting stack for the DevPulse application, fully optimized for local Docker Compose development and ready for Kubernetes deployment (Rancher & Azure cloud).

Key Features Implemented:

• Prometheus Instrumentation: Enabled metrics scraping endpoints across all three Spring Boot services and the Python microservice.
• Auto-Provisioned Dashboards: Created three Grafana dashboards (devpulse_dashboard.json, devpulse_resources_dashboard.json, azure_sizing_dashboard.json) loaded automatically at startup.
• Kubernetes Sizing & Resource Monitoring: Re-routed Azure VM sizing/estimations and resource dashboards to query Kubernetes-specific cAdvisor metrics (container_memory_working_set_bytes and container_cpu_usage_seconds_total) from the setops namespace, ensuring database (postgres) and message broker (rabbitmq) metrics are tracked accurately.
• Namespace Isolated Alerts: Added alerting rules for downtime, restarts, and OOM kills in the setops namespace, routed through custom HTML templates to a Telegram chat point.

Visual Evidence:

1. System Monitoring & Client Log Ingestion

Split-screen displaying log ingestion throughput/latency metrics on Grafana (left) alongside the DevPulse React UI displaying AI insights (right):

2. Azure VM Sizing & Capacity Planning

Dynamic Azure VM size recommender calculating resource budgets by aggregating actual container memory footprints:

3. Service Runtime Resource Utilization

Granular monitoring of JVM heap usage, Hikari connection pools, thread counts, and FastAPI resource consumption:

4. Custom Telegram Notifications in Action

Telegram channel displaying firing system outage alerts and instant recovery notifications formatted with the custom HTML template:

Component

• Client: client/
• API contract: api/
• Spring ingestion: services/spring-ingestion/
• Spring logbook: services/spring-logbook/
• Spring alerts: services/spring-alerts/
• GenAI: services/py-intelligence/
• Infrastructure: infra/
• CI/CD: .github/workflows/
• Documentation

API Impact

• This changes the API.
• api/openapi.yaml was updated.
• This does not change the API.

Testing

• I tested this locally.
• I added or updated tests.
• Tests are not applicable for this change.

Checklist

• Branch name follows (feat|fix)/(issue_id)/(name_of_issue).
• The change is limited to the intended component(s).
• Documentation was updated if needed.

Related Issue

Closes #15

[tahahundekari]

LGTM! Thank you!

[sachmii]

Looks good, LGTM