chore: workspace 加 gui 成员，qr-core 加 serde

Cargo.toml

@@ -1,6 +1,6 @@
 [workspace]
 resolver = "2"
-members = ["core", "cli"]
+members = ["core", "cli", "gui"]
 
 [workspace.package]
 version = "0.1.0"

core/Cargo.toml

@@ -7,5 +7,6 @@ authors.workspace = true
 
 [dependencies]
 image = { version = "0.25", default-features = false, features = ["png"] }
+serde = { version = "1", features = ["derive"] }
 
 [dev-dependencies]

core/src/version.rs

@@ -1,7 +1,8 @@
 use std::sync::OnceLock;
+use serde::Serialize;
 
 /// 纠错级别
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize)]
 pub enum EcLevel {
     L, // 约 7%
     M, // 约 15%
@@ -22,7 +23,7 @@ impl EcLevel {
 }
 
 /// 版本号 1~40
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize)]
 pub struct Version(pub u8);
 
 impl Version {

gui/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "qr-gui"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+authors.workspace = true
+
+[dependencies]
+qr-core = { path = "../core" }
+serde = { version = "1", features = ["derive"] }
+
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
+eframe = { version = "0.31", default-features = false, features = ["default_fonts"] }
+egui = { version = "0.31" }
+egui_extras = { version = "0.31", features = ["image"] }
+image = { version = "0.25", default-features = false, features = ["png"] }
+rfd = "0.15"

gui/src/app.rs

@@ -0,0 +1,16 @@
+//! QRGen 主应用 — eframe 入口
+
+use eframe::egui;
+
+/// QR 码生成器应用
+#[derive(Default)]
+pub struct QRGenApp;
+
+impl eframe::App for QRGenApp {
+    fn update(&mut self, ctx: &egui::Context, _frame: &mut eframe::Frame) {
+        egui::CentralPanel::default().show(ctx, |ui| {
+            ui.heading("QR 码生成器");
+            ui.label("GUI 待实现");
+        });
+    }
+}

gui/src/lib.rs

@@ -0,0 +1,6 @@
+//! QR Code GUI — eframe/egui 桌面应用
+
+pub mod app;
+
+// Re-export main entry
+pub use app::QRGenApp;