docs: change navigating CONTRIBUTING file to CONTRIBUTING.md

Author: vikashkrdeveloper

README.md

@@ -217,7 +217,7 @@ We welcome contributions from developers of all skill levels! Whether you're fix
 - **Write tests**: Keep coverage high
 - **Update docs**: If you change or add features
 
-See the [Contributing Guide](CONTRIBUTING) for more details.
+See the [Contributing Guide](CONTRIBUTING.md) for more details.
 
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