Replace the fixed [256]byte carry buffer with a dynamic []byte slice to support arbitrarily long lines without heap allocation during accumulation. Update all carry buffer handling logic to use len(s.carry) and append instead of fixed-size copy operations.
This commit refactors the rope scanner implementation by renaming gbRopeScanner to ropeScanner and extracting the common functionality into a new file. It also introduces a new FastqChunkParserRope function that parses FASTQ chunks directly from a rope without Pack(), enabling more efficient memory usage. The existing parsers are updated to use the new rope-based parser when available. The BioSequence type is enhanced with a TakeQualities method for more efficient quality data handling.