Add AST-based dataflow diagram generation for documentation

[archit7-beep]

Describe your changes

This PR introduces an initial prototype for generating dataflow diagrams from the codebase using an AST-based approach to improve documentation clarity.

The implementation extracts method-level relationships (e.g., process_step) and generates Mermaid-based diagrams representing how data flows through different components.

This work complements the ongoing structured documentation efforts by adding visual context to better understand model and pipeline behavior.

##Example of Digrams

🔁 Data Flow

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🏗️ Structure Diagram

Motivation:
While current documentation improves structure and API visibility, understanding data flow still requires manual code tracing. This approach aims to make data pipelines easier to understand and improve onboarding for new contributors.

Dependencies:

• Python AST (built-in)
• Mermaid (for diagram rendering)

Issue Link

Related to ( #61 )

Type of change

• 🐛 Bug fix (non-breaking change that fixes an issue)
• ✨ New feature (non-breaking change that adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to not work as expected)
• 📖 Documentation (Addition or improvements to documentation)

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[joeloskarsson]

Hi, could you add pictures of the diagrams here in the PR, so it is easier to get an idea of what they contain?

[archit7-beep]

Hi, could you add pictures of the diagrams here in the PR, so it is easier to get an idea of what they contain?

@joeloskarsson I have updated the diagrams in description of PR