Dispatch prefixed multi, exec, and discard commands without changing
Redis transaction state. Forward all arguments through the wrappers so
module commands retain their original call semantics.

Add regression tests for direct and pipelined module commands, argument
encoding, and connection pooling with and without an open transaction.
The tests use a mock Redis server without requiring an external module.

Validated 372 assertions across HTTP and stream, including RedisBloom
integration tests, plus real module probes for mixed pipelines,
cancellation, rejected commands, and connection reuse. Lua lint and
whitespace checks passed.