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/src/components/base/collapse.svelte

@@ -6,6 +6,7 @@
         key: string;
         icon?: string | Snippet;
         title: string | Snippet;
+        titleHelp?: string;
         description?: string | Snippet;
         content: string | Snippet;
     }
@@ -47,6 +48,15 @@
                 {/if}
 
                 <Render target={item.title} />
+                {#if item.titleHelp}
+                    <span
+                        class="tf-collapse-item-title-help"
+                        data-help={item.titleHelp}
+                        aria-label="节点使用说明"
+                    >
+                        ?
+                    </span>
+                {/if}
 
                 <span class="tf-collapse-item-title-arrow {activeKeys.includes(item.key) ? 'rotate-90' : ''}">
                     <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="currentColor"><path
@@ -75,4 +85,70 @@
         transform: rotate(90deg);
         transition: transform 0.3s ease;
     }
+
+    .tf-collapse-item-title-help {
+        margin-left: 6px;
+        width: 16px;
+        height: 16px;
+        border-radius: 50%;
+        border: 1px solid #c6cfdd;
+        color: #64748b;
+        display: inline-flex;
+        align-items: center;
+        justify-content: center;
+        font-size: 11px;
+        line-height: 1;
+        cursor: default;
+        user-select: none;
+        background: #fff;
+        position: relative;
+    }
+
+    .tf-collapse-item-title-help:hover {
+        border-color: #94a3b8;
+        color: #334155;
+        background: #f8fafc;
+    }
+
+    .tf-collapse-item-title-help::after {
+        content: attr(data-help);
+        position: absolute;
+        left: calc(100% + 10px);
+        top: 50%;
+        transform: translateY(-50%);
+        min-width: 260px;
+        max-width: 420px;
+        white-space: pre-line;
+        background: #0f172a;
+        color: #f8fafc;
+        border-radius: 8px;
+        padding: 10px 12px;
+        font-size: 12px;
+        line-height: 1.45;
+        box-shadow: 0 8px 22px rgba(2, 6, 23, 0.25);
+        opacity: 0;
+        visibility: hidden;
+        pointer-events: none;
+        z-index: 120;
+    }
+
+    .tf-collapse-item-title-help::before {
+        content: "";
+        position: absolute;
+        left: calc(100% + 4px);
+        top: 50%;
+        transform: translateY(-50%);
+        border-top: 6px solid transparent;
+        border-bottom: 6px solid transparent;
+        border-right: 6px solid #0f172a;
+        opacity: 0;
+        visibility: hidden;
+        z-index: 121;
+    }
+
+    .tf-collapse-item-title-help:hover::after,
+    .tf-collapse-item-title-help:hover::before {
+        opacity: 1;
+        visibility: visible;
+    }
 </style>