Bug #1: Fix worker count logic in generic_consumer
- Was: min 2 (max 500 n_workers) - always created 2 workers
- Now: max 2 (min 500 n_workers) - properly clamps between 2-500
- Impact: Worker configuration was completely ignored
Bug #2: Handle missing dot in __FUNCTION__ name
- Added exception handling for String.rindex in trace span creation
- Prevents crash when tracing top-level or non-module functions
- Uses option type for module_path when no dot is present
- Scoped try/catch to only parsing logic