dsh-connect-opencode-free: Integrating OpenCode Zen's Free Models into DeepSeek Harness

The DeepSeek Harness (DSH) plugin `dsh-connect-opencode-free` is designed to simplify the process of connecting to OpenCode Zen’s free models. It can be used without a Key and supports spoofed authentication, real-time dual-source model discovery, visual management in the settings page, and one-click Provider configuration. The plugin provides three tiers of usage rules (using only the public quota by default) and allows flexible switching of billing sources. To install it, add the dependency via the profile’s `package.json`, then restart DSH to synchronize and configure models in the settings.