Package-level declarations

ZIP reader over a seekable RandomAccessSource (+ZIP64). Reads the central directory at the tail (the authoritative record), so entries is a cheap "browse without extract", and read seeks to a single local header for partial extract. This reader decodes STORE and DEFLATE. Other methods appear in entries, but read throws for them.

ZIP writer for STORE and DEFLATE entries, with ZIP64 where it is needed. The whole archive is built in memory and returned as a ByteArray; there is no streaming form. ZIP64 records are emitted only when the entry count passes 65535 or a size or offset overflows 32 bits, with per-entry ZIP64 extra fields for oversized entries, so ordinary archives stay classic and small.