docs: 修正全部文档使其与源码实现一致

- Plugin.Start(sdk *PluginSDK) 接口签名改为指针
- 方法表重写: 移除 CallLLM/QueryKnowledge/SetMemory 等不存在方法
- IOInjector 参数顺序修正为 (source, channel, text)
- 删除虚构 SDKConfig, 替换为实际 New() 构造函数签名
- .hmap 内容描述一致化 (plugin.so + plugin.dll + main.lua)
- 添加 meta/ 包元数据文件

example/sanitizer/plg.json

@@ -0,0 +1,11 @@
+{
+  "name": "sanitizer",
+  "name_zh": "输出清洗",
+  "name_en": "sanitizer",
+  "version": "0.1.0",
+  "description": "清洗 LLM 输出中的工具调用残留（思维泄漏）",
+  "author": "HomeAgent SDK",
+  "entry": "plugin.so",
+  "tags": ["sanitizer"],
+  "targets": "linux/amd64"
+}