Add CODEOWNERS file

.github/CODEOWNERS

@@ -0,0 +1,31 @@
+# Default permissions for all files not matched below
+* @newrelic/dotnet @newrelic/go-agent @newrelic/java-agent @newrelic/node-js-agent @newrelic/php-agent @newrelic/python @newrelic/ruby-agent
+
+# Team based ownership
+/.github/workflows/dotnet.yml @newrelic/dotnet
+/src/dotnet/ @newrelic/dotnet
+/tests/dotnet/ @newrelic/dotnet
+
+/.github/workflows/go.yml @newrelic/go-agent
+/src/go/ @newrelic/go-agent
+/tests/go/ @newrelic/go-agent
+
+/.github/workflows/java.yml @newrelic/java-agent
+/src/java/ @newrelic/java-agent
+/tests/java/ @newrelic/java-agent
+
+/.github/workflows/nodejs.yml @newrelic/node-js-agent
+/src/nodejs/ @newrelic/node-js-agent
+/tests/nodejs/ @newrelic/node-js-agent
+
+/.github/workflows/php.yml @newrelic/php-agent
+/src/php/ @newrelic/php-agent
+/tests/php/ @newrelic/php-agent
+
+/.github/workflows/python.yml @newrelic/python
+/src/python/ @newrelic/python
+/tests/python/ @newrelic/python
+
+/.github/workflows/ruby.yml @newrelic/ruby-agent
+/src/ruby/ @newrelic/ruby-agent
+/tests/ruby/ @newrelic/ruby-agent