chore: reorganize .fernignore for better maintainability

Author: AlePouroullis

.fernignore

@@ -1,32 +1,38 @@
-# Specify files that shouldn't be modified by Fern
-
-
-## Custom code
-
-src/humanloop/evals
-src/humanloop/prompt_utils.py
-src/humanloop/path_utils.py
+# Files and directories that should not be modified by Fern
+# Fern is an OpenAPI SDK generator that automatically creates and updates SDK code
+# from our OpenAPI specification. This file controls which files are excluded from
+# Fern's auto-generation process to prevent overwriting custom implementations.
+
+## Core SDK Implementation
+# Custom implementation files that should not be auto-generated by Fern
+# These files contain our custom logic and should be manually maintained
 src/humanloop/client.py
-src/humanloop/overload.py
 src/humanloop/context.py
+src/humanloop/decorators/
 src/humanloop/error.py
+src/humanloop/evals/
+src/humanloop/otel/
+src/humanloop/overload.py
+src/humanloop/path_utils.py
+src/humanloop/prompt_utils.py
+src/humanloop/sync/
+src/humanloop/cli/
+
+## Development Tools
+# Configuration and tooling files
 mypy.ini
-README.md
-src/humanloop/decorators
-src/humanloop/otel
-src/humanloop/sync
-src/humanloop/cli
 pytest.ini
 
-## Tests
+## Documentation
+# Documentation files that should be manually maintained
+README.md
 
-tests/custom
+## Testing
+# Custom test implementations
+tests/custom/
 tests/__init__.py
 
-## CI
-
-.github/workflows/ci.yml
-
-## Config
-
+## Version Control and CI
+# Version control and CI configuration
 .gitignore
+.github/workflows/ci.yml