Align GeoDebug repository contracts

[GeoGeekLab]

Summary

• add the same MIT license used by GeoGeekLab/engineering-quality
• add GeoDebug-specific CONTRIBUTING.md and SECURITY.md
• add a pull request template aligned with the GeoGeekLab engineering contract
• declare MIT in Python package metadata and include the license file in distributions
• add MIT / contributing / security / license entry points to the README
• align badge styling without changing GeoDebug's product positioning

Scope

The repository-level conventions follow GeoGeekLab/engineering-quality, while contribution and security guidance is specialized for GeoDebug's adapters, rule engine, deep scans, schemas, and geospatial semantics.