Implement basic event ingestion module in Rust

[AbdulSnk]

Overview

StreamForge Core needs a foundational event ingestion module responsible for receiving and parsing contribution events (e.g. commits, pull requests, reviews) from upstream sources.

What needs to be done

• Create an ingestion module under src/
• Define a basic Event struct with the following fields:
  • id (String)
  • event_type (String — e.g. "pull_request", "commit", "review")
  • contributor (String)
  • timestamp (u64)
  • metadata (optional key-value map)
• Implement a function to receive and parse a raw event into the Event struct
• Handle malformed or missing fields gracefully with proper error types

Acceptance Criteria

• src/ingestion.rs module exists and is wired into main.rs
• Event struct is defined with the fields listed above
• Parsing function correctly handles valid and invalid inputs
• Unit tests cover at least: valid event, missing field, malformed input

Pre-Submission Checklist

• I have run cargo build locally and it succeeds
• I have run cargo test locally and all tests pass
• I have run cargo fmt to format my code
• I have run cargo clippy and fixed all warnings

Notes

This is the foundational building block of StreamForge Core. Keep the implementation simple and well-documented.