dsh-second-brain: DeepSeek Harness Second Brain Loader

This plugin is designed to inject a local “brain” snapshot (identity, state, etc.) into every new DeepSeek Harness (DSH) session, enabling cross-session memory. It runs as a read-only, zero-dependency, pure ESM module, injecting the snapshot into the system prompt via hooks while enforcing a 300-character minimum and a 1000-character maximum to prevent overflow. It is enabled by default after installation; new sessions automatically include the snapshot content, and users can verify the effect with specific commands.