dsh-compaction-meta: Meta Compaction Plugin

The Meta-Compression plugin for DeepSeek Harness aims to give the model active control over context, replacing passive threshold-triggered compaction. Currently in a skeletal stage, its core features include listing the context, allowing the model to edit specified context ranges, and disabling passive compaction. It is planned as the third Provider for the compaction seam, intended to be used with a skill, and to provide a metacognitive interface for long-term learning agents. It can be installed by adding it via the dsh command.