dsh-plugin-llm-balance: Persistent Display of API Balance and Quota in DSH Web GUI

`dsh-plugin-llm-balance` is a plugin for the DSH (DeepSeek Harness) Web GUI, designed to centrally display the balances and quotas of multiple providers including DeepSeek, Moonshot, Kimi For Coding, OpenAI Codex, and OpenCode Go. The plugin provides a draggable floating card in the upper-right corner of the page, which automatically shows data from the three most recently used providers. It supports the visualization of monetary balances and package quotas (including 5-hour windows, weekly windows, and reset times), and adjusts colors in tiers based on thresholds to indicate resource status. The plugin features auto-refresh (default 60 seconds), position memory, and the DeepSeek peak/off-peak electricity price badge. Its core security feature lies in strict credential isolation: API keys and OAut