#3622 refactor: Split type parameters for Singer reader and writer protocols Pull request opened by edgarrmondragon Summary by Sourcery Refine the generic reader and writer protocols for Singer message encoding to use separate, more precise type parameters for input and output streams, and align the msgspec-based writer to use bytearray-based JSONL serialization. Bug Fixes: • Correct the msgspec JSONL serialization return type to match the actual bytearray buffer used for encoding, ensuring type safety for writer implementations. Enhancements: • Split the shared type parameter for Singer readers and writers into distinct reader and writer type variables, allowing writers to support bytearray while keeping readers constrained to str and bytes. • Adjust the msgspec-based Singer writer to use bytearray as its message format type in line with the updated generic writer protocol. meltano/sdk