桌面 GUI 外链修复 + 主题顺序调整（含结构扁平化进行中的工作区基线）

- 集成 tauri-plugin-opener：Cargo/lib.rs/capabilities/npm 四处接线，新增 src/openExternal.ts（桌面走 opener，浏览器回退 window.open，相对路径绝对化）
- 关于页 4 个链接、活动栏官网菜单、代理错误横幅 2 处健康检查链接全部改走 openExternal，桌面端可正常跳转
- 设置→外观 主题顺序调整为 深色/浅色/跟随系统
- release 二进制重编并验证（浏览器实测关于页链接可开文档页）
- 附带工作区中未提交的扁平化重构现状（另一会话进行中）
- homepage 落地页与文档终检通过（8787 / 与 /docs 双 200）

src-tauri/src/models.rs

@@ -0,0 +1,64 @@
+use serde::{Deserialize, Serialize};
+use std::collections::HashMap;
+
+#[derive(Debug, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct BodySpec {
+    pub mode: String,
+    pub raw: Option<String>,
+}
+
+#[derive(Debug, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct HttpSpec {
+    pub method: String,
+    pub url: String,
+    #[serde(default)]
+    pub headers: HashMap<String, String>,
+    pub query: Option<HashMap<String, String>>,
+    pub body: Option<BodySpec>,
+    pub timeout_ms: Option<u64>,
+    pub proxy: Option<ProxySettings>,
+}
+
+#[derive(Debug, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct HttpResult {
+    pub status: u16,
+    pub headers: HashMap<String, String>,
+    pub body: String,
+    pub time_ms: u128,
+    pub size: usize,
+}
+
+#[derive(Debug, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct WsSpec {
+    pub url: String,
+    pub protocols: Option<Vec<String>>,
+    #[serde(default)]
+    pub headers: HashMap<String, String>,
+}
+
+#[derive(Clone, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct WsEvent {
+    pub session_id: String,
+    pub kind: String,
+    pub data: String,
+}
+
+#[derive(Debug, Deserialize)]
+pub struct ProxySettings {
+    pub mode: String,
+    pub http: String,
+    pub https: String,
+    pub bypass: String,
+    pub auth: Option<ProxyAuth>,
+}
+
+#[derive(Debug, Deserialize)]
+pub struct ProxyAuth {
+    pub username: String,
+    pub password: String,
+}