[ITEP-74332] Add healthcheck to controller

[jakubsikorski]

📝 Description

Adds a healthcheck to scene controller.

Manager and autocalibration already have healthchecks implemented.

✨ Type of Change

Select the type of change your PR introduces:

• 🐞 Bug fix – Non-breaking change which fixes an issue
• 🚀 New feature – Non-breaking change which adds functionality
• 🔨 Refactor – Non-breaking change which refactors the code base
• 💥 Breaking change – Changes that break existing functionality
• 📚 Documentation update
• 🔒 Security update
• 🧪 Tests
• 🚂 CI

🧪 Testing Scenarios

Describe how the changes were tested and how reviewers can test them too:

• ✅ Tested manually
• 🤖 Ran automated end-to-end tests

✅ Checklist

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• 🔍 PR title is clear and descriptive
• 📝 For internal contributors: If applicable, include the JIRA ticket number (e.g., ITEP-123456) in the PR title. Do not include full URLs
• 💬 I have commented my code, especially in hard-to-understand areas
• 📄 I have made corresponding changes to the documentation
• ✅ I have added tests that prove my fix is effective or my feature works

[Copilot]

Pull request overview

This PR adds HTTP-based health check functionality to the scene controller service, bringing it in line with other services (manager and autocalibration) that already have health checks implemented.

Changes:

• Adds an HTTP server with /healthz and /health endpoints to the controller
• Configures health check probes in both Docker Compose and Kubernetes deployment manifests
• Implements a command-line argument --healthcheck-port to enable/configure the health check server

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
controller/src/controller-cmd	Implements HTTP health check server with request handler and threading support
sample_data/docker-compose-dl-streamer-example.yml	Adds Docker health check configuration using the new endpoint
kubernetes/scenescape-chart/templates/scene-controller/deployment.yaml	Replaces placeholder readiness probe with HTTP-based health check

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.