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

tools/plugindev/templates/README.md.tmpl

@@ -0,0 +1,19 @@
+# {{.Plg.Name}}
+
+{{.Plg.Description}}
+
+## Build
+
+```bash
+plugindev build
+```
+
+## Install
+
+Upload the `.hmap` file through the Plugin Manager API:
+
+```bash
+curl -X POST http://localhost:8080/api/v1/plugins \
+  -H "Content-Type: application/octet-stream" \
+  --data-binary @dist/<name_en_snake>_linux_amd64.hmap
+```