Function blosc2_schunk_insert_chunk 

pub unsafe extern "C" fn blosc2_schunk_insert_chunk(
    schunk: *mut blosc2_schunk,
    nchunk: i64,
    chunk: *mut u8,
    copy: bool,
) -> i64

@brief Insert a chunk at a specific position in a super-chunk.

@param schunk The super-chunk where the chunk will be appended. @param nchunk The position where the chunk will be inserted. @param chunk The @p chunk to insert. If an internal copy is made, the @p chunk can be reused or freed if desired. @param copy Whether the chunk should be copied internally or can be used as-is.

@return The number of chunks in super-chunk. If some problem is detected, this number will be negative.