dsh-compactor: A Context Compression Plugin for DeepSeek Harness

The DeepSeek Harness plugin `dsh-compactor` is designed to address context bloat and infinite-loop issues in long conversations. It employs a three-tier processing mechanism (real-time pruning, batch summarization, and archive restoration) and offers two modes: API-based summarization and local rule-based compression. The plugin supports semantic understanding, data rollback, and infinite-loop detection, and requires user confirmation before compression is executed to balance context length with information retention.