feat: Adds serde_yaml dependency and implement YAML configuration loa…

[Murasko]

Adds serde_yaml dependency and removes the lum_config FileHandler.

[Copilot]

Pull Request Overview

This PR replaces the lum_config FileHandler with direct YAML configuration loading using serde_yaml. The change simplifies configuration management by removing a dependency layer and implementing custom YAML file handling logic.

Key changes:

• Removes FileHandler dependency from lum_config and adds serde_yaml dependency
• Implements custom config file loading with automatic directory creation and default config generation
• Adds example YAML configuration file showing the expected format

Reviewed Changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated 2 comments.

File	Description
src/main.rs	Replaces FileHandler with custom YAML config loading logic and adds new error variants
example-config.yaml	Provides example configuration showing YAML structure and available options
Cargo.toml	Adds serde_yaml dependency

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[Kitt3120]

Thanks for the contribution. I made some recommendations. We should also think about adding yaml support in lum_config upstream instead of implementing it here. But that's up to the future, implementing it here is okay for now :)

[Copilot]

Pull Request Overview

Copilot reviewed 4 out of 5 changed files in this pull request and generated 2 comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 10 out of 11 changed files in this pull request and generated 2 comments.

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