dsh-context-governor: Session Context and Cost Monitoring for DeepSeek Harness

dsh-context-governor is a DeepSeek Harness plugin designed to provide an intuitive overview of session context and cost estimation. It displays prompt size, cache hit rate, cost multiplier, and context pressure in real time, helping developers make informed decisions before compacting or retrying. It does not consume tokens; it calculates metrics solely by reading DSH projection data. It also supports viewing balance, rates, and pressure indicators in the Web interface to help manage the context budget.