Function embed_in_memory 

pub fn embed_in_memory(
    payload_input: &mut dyn Read,
    cover_input: &mut dyn Read,
    output: &mut dyn Write,
    technique: &dyn EmbedTechnique,
) -> Result<(), OpsecError>

Run the embed pipeline entirely in memory.

1. Reads cover and payload from their respective readers.
2. Embeds payload into cover using the given technique.
3. Writes the stego output to output.
4. Zeroizes all intermediate buffers.

Errors

Returns OpsecError::PipelineError if any step fails.