docs: Add CONTRIBUTING.md

CONTRIBUTING.md

@@ -0,0 +1,26 @@
+Contributing to bdi-kit
+=======================
+
+There are many ways to contribute to bdi-kit, such as improving the codebase, reporting 
+issues or bugs, enhancing the documentation, reviewing pull requests from other developers, 
+adding new matching methods, or expanding support for additional standards. 
+See the instructions below to get started!
+
+
+Adding New Matching Methods
+---------------------------
+
+Contributors can add new methods for schema and value matching by following these steps:
+
+1. Create a Python module inside the `algorithms` folder (e.g., `bdikit/value_matching/algorithms`).
+
+2. Define a class in the module that implements either `BaseValueMatcher` (for value matching) or `BaseSchemaMatcher` (for schema matching).
+
+3. Instantiate an object of your class in `matcher_factory.py` (e.g., `bdikit/value_matching/matcher_factory.py`). Ensure your module is properly imported in the `__init__.py` file (e.g.,` bdikit/value_matching/__init__.py`).
+
+
+Code of Conduct
+---------------
+
+We abide by the principles of openness, respect, and consideration of others
+of the Python Software Foundation: https://www.python.org/psf/codeofconduct/.