feat: 增强代码节点编辑器与放大阅读体验

- tinyflow-ui: 新增 CodeScriptEditor（CodeMirror 6）并支持语法高亮、上下文补全、自动括号与 _result 高亮

- tinyflow-ui: 代码节点接入引擎能力列表与节点说明提示，统一 JS/Python 编辑体验

- tinyflow-ui: 增加放大编辑模式，支持居中弹层、ESC 与点击外部关闭

- app/workflow: 对接 supportedCodeEngines 能力并透传 codeEngine provider

easyflow-ui-admin/packages/tinyflow-ui/package.json

@@ -40,6 +40,13 @@
     "vite-plugin-dts": "^4.5.4"
   },
   "dependencies": {
+    "@codemirror/autocomplete": "^6.18.7",
+    "@codemirror/commands": "^6.8.1",
+    "@codemirror/lang-javascript": "^6.2.4",
+    "@codemirror/lang-python": "^6.2.1",
+    "@codemirror/language": "^6.11.3",
+    "@codemirror/state": "^6.5.2",
+    "@codemirror/view": "^6.38.6",
     "@floating-ui/dom": "^1.7.4",
     "@xyflow/svelte": "^1.4.2"
   },