- Add `PayloadFinalizer` to apply configuration rules at the final serialization barrier
- Support decoding, modifying, and re-encoding Devin protobuf business fields
- Add multipart form-data payload normalization to JSON for media payload rules
Closes: #5067
- Removed deprecated interceptor and executor-related methods, including `callRequestInterceptor`, `callResponseInterceptor`, and `callStreamChunkInterceptor`.
- Consolidated unused logic and pruned redundant imports to streamline `adapters.go`.
- No functional changes.