feat: add Dockerized ETL ingestion stack

[ZeroQuest]

This PR introduces a Dockerized deployment workflow for the ETL pipeline, allowing the ingestion stack to run in a consistent, containerized environment. It also includes supporting refactors to improve pipeline portability, reduce log noise, and reorganize sample data.

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Features

Dockerized ETL stack

• Added Docker support for the ETL ingestion pipeline
• Containerized application dependencies and runtime environment
• Simplified local setup and execution through Docker
• Established a consistent execution environment across development machines

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Refactor

Pipeline robustness

• Improved pipeline behavior to support execution within a containerized environment
• Updated file handling and runtime assumptions to be Docker-compatible
• Preserved existing ETL functionality during infrastructure changes

Sample data organization

• Moved sample datasets into dedicated data source locations
• Improved separation between application code and ingestion data
• Simplified management of test and demonstration datasets

Logging improvements

• Reduced unnecessary verbosity in ETL logging output
• Improved readability of pipeline execution logs
• Retained key operational and error information

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Code quality

• Applied Black formatting across the codebase
• Ensured Ruff linting compliance
• Cleaned up minor inconsistencies introduced during refactoring

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Repository maintenance

Git configuration

• Added coverage artifacts to .gitignore
• Prevented generated coverage files from being tracked in version control

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Dependencies

• Added Docker configuration required to run the ETL pipeline in a containerized environment
• No changes to core ETL processing dependencies

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Testing

• Verified ETL pipeline executes successfully within Docker environment
• Confirmed existing ingestion workflows remain functional after refactoring
• Validated sample data remains accessible through updated source locations
• Ensured logging output remains useful while reducing noise

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