findHCSequences

private fnLz4Sequence[] findHCSequences(const(ubyte)[] src, uint hashBits)

Find sequences using a lazy matching algorithm (HC mode).

This implements the LZ4 High Compression (HC) strategy used for levels 7-9. Unlike greedy matching, lazy matching defers the decision to emit a match: after finding a match at position P, it checks if position P+1 has a longer match. If so, the byte at P is emitted as a literal and the better match at P+1 is used instead.

This approach trades compression speed for better compression ratios, as it can find longer matches that span across initial match positions.

The algorithm ensures the last LZ4_MIN_MATCH bytes are emitted as literals (LZ4 format requirement for safe decoding).

Parameters

`src`	Input data to compress.
`hashBits`	Number of hash bits for the table (determines table size).

Returns

An array of Lz4Sequence structs describing the compressed

representation. The final sequence will have matchLen == 0.