feat(backend): 新增 QuickJS 运行时支持 JavaScript 执行器

refactor(backend): 重构 script_js 执行器实现 JavaScript 文件/内联脚本执行
feat(backend): 变量节点支持表达式/引用快捷语法输入
docs: 添加变量节点使用文档说明快捷语法功能
style(frontend): 调整测试面板样式和布局
fix(frontend): 修复测试面板打开时自动关闭节点编辑侧栏
build(backend): 添加 rquickjs 依赖用于 JavaScript 执行

backend/Cargo.lock

@@ -2492,6 +2492,33 @@ dependencies = [
  "serde_derive",
 ]
 
+[[package]]
+name = "rquickjs"
+version = "0.8.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d16661bff09e9ed8e01094a188b463de45ec0693ade55b92ed54027d7ba7c40c"
+dependencies = [
+ "rquickjs-core",
+]
+
+[[package]]
+name = "rquickjs-core"
+version = "0.8.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6c8db6379e204ef84c0811e90e7cc3e3e4d7688701db68a00d14a6db6849087b"
+dependencies = [
+ "rquickjs-sys",
+]
+
+[[package]]
+name = "rquickjs-sys"
+version = "0.8.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4bc352c6b663604c3c186c000cfcc6c271f4b50bc135a285dd6d4f2a42f9790a"
+dependencies = [
+ "cc",
+]
+
 [[package]]
 name = "rsa"
 version = "0.9.8"
@@ -3865,6 +3892,7 @@ dependencies = [
  "regex",
  "reqwest",
  "rhai",
+ "rquickjs",
  "sea-orm",
  "serde",
  "serde_json",