dsh-strip-sandbox-permissions: Strip Sandbox Permission Fields to Avoid False Rejections

`dsh-strip-sandbox-permissions` is a zero-dependency DeepSeek Harness (DSH) plugin designed to resolve false sandbox rejections caused by the `sandbox_permissions` field and its `justification` field included in model tool-call parameters. Positioned in the `llm/stream` waterfall flow, it removes these two fields after tool-call parameters are parsed, thereby preventing erroneous interruptions caused by non-strict permission broadening. It is fault-tolerant and modifies only valid objects, is licensed under the MIT License, can be installed via npm, and requires DSH to be restarted to take effect.