Module compression 

Block-level compression and mode dispatch (N, Z, 4, E, F). Block-level compression and mode dispatch for BLTE.

Each BLTE block starts with a one-byte mode prefix:

• N (0x4E) - raw / uncompressed data, returned as-is.
• Z (0x5A) - zlib-compressed data (RFC 1950).
• 4 (0x34) - LZ4 block compression with sub-block framing.
• E (0x45) - encrypted block; after decryption the inner payload is recursively decoded (its first byte is the inner compression mode).
• F (0x46) - recursive BLTE (not currently supported).

Functions

decode_block

Decode a BLTE block based on its mode byte (no encryption support).

decode_block_with_keys

Decode a BLTE block with optional encryption support.