feat: JSON 数据树形展示，可折叠/展开

改进：
- 树形结构展示 JSON 数据，层级清晰
- 点击三角形折叠/展开节点
- 悬停显示复制按钮，可复制单个字段
- 长字符串自动截断（超过 100 字符）
- 显示数组/对象的项数统计
- 更好的可读性和交互体验

web/index.html

@@ -275,21 +275,69 @@
             gap: 10px;
         }
 
-        /* JSON 展示样式 */
+        /* JSON 树形展示样式 */
         .json-viewer {
             background: #f8f9fa;
             border-radius: 8px;
             padding: 20px;
             font-family: 'Courier New', monospace;
-            font-size: 13px;
+            font-size: 14px;
-            line-height: 1.6;
+            line-height: 1.8;
             overflow-x: auto;
             max-height: 60vh;
         }
 
+        .json-line {
+            display: flex;
+            align-items: center;
+            padding: 2px 0;
+            position: relative;
+        }
+
+        .json-line:hover {
+            background: rgba(102, 126, 234, 0.05);
+        }
+
+        .json-indent {
+            display: inline-block;
+            width: 20px;
+            flex-shrink: 0;
+        }
+
+        .json-toggle {
+            display: inline-block;
+            width: 20px;
+            height: 20px;
+            text-align: center;
+            cursor: pointer;
+            user-select: none;
+            color: #999;
+            flex-shrink: 0;
+            font-size: 12px;
+            line-height: 20px;
+        }
+
+        .json-toggle:hover {
+            color: #667eea;
+        }
+
+        .json-toggle.collapsed::before {
+            content: '▶';
+        }
+
+        .json-toggle.expanded::before {
+            content: '▼';
+        }
+
         .json-key {
             color: #0066cc;
             font-weight: bold;
+            margin-right: 8px;
+        }
+
+        .json-separator {
+            color: #999;
+            margin: 0 4px;
         }
 
         .json-string {
@@ -308,6 +356,46 @@
             color: #6f42c1;
         }
 
+        .json-bracket {
+            color: #666;
+            font-weight: bold;
+        }
+
+        .json-copy-btn {
+            opacity: 0;
+            margin-left: 10px;
+            padding: 2px 8px;
+            font-size: 11px;
+            background: #667eea;
+            color: white;
+            border: none;
+            border-radius: 3px;
+            cursor: pointer;
+            transition: opacity 0.2s;
+        }
+
+        .json-line:hover .json-copy-btn {
+            opacity: 1;
+        }
+
+        .json-copy-btn:hover {
+            background: #5568d3;
+        }
+
+        .json-children {
+            display: block;
+        }
+
+        .json-children.collapsed {
+            display: none;
+        }
+
+        .json-summary {
+            color: #999;
+            font-style: italic;
+            margin-left: 8px;
+        }
+
         /* Toast 通知 */
         .toast {
             position: fixed;
@@ -525,28 +613,131 @@
             document.getElementById(modalId).classList.remove('active');
         }
 
-        // JSON 格式化显示
+        // JSON 树形渲染
-        function syntaxHighlight(json) {
+        function renderJSONTree(obj, level = 0) {
-            if (typeof json !== 'string') {
+            const lines = [];
-                json = JSON.stringify(json, null, 2);
+            const indent = ' '.repeat(level * 2);
+            
+            if (obj === null) {
+                return `<span class="json-null">null</span>`;
             }
             
-            json = json.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;');
+            if (typeof obj !== 'object') {
-            
+                if (typeof obj === 'string') {
-            return json.replace(/("(\\u[a-zA-Z0-9]{4}|\\[^u]|[^\\"])*"(\s*:)?|\b(true|false|null)\b|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?)/g, function (match) {
+                    return `<span class="json-string">"${escapeHtml(obj)}"</span>`;
-                let cls = 'json-number';
+                } else if (typeof obj === 'number') {
-                if (/^"/.test(match)) {
+                    return `<span class="json-number">${obj}</span>`;
-                    if (/:$/.test(match)) {
+                } else if (typeof obj === 'boolean') {
-                        cls = 'json-key';
+                    return `<span class="json-boolean">${obj}</span>`;
-                    } else {
-                        cls = 'json-string';
-                    }
-                } else if (/true|false/.test(match)) {
-                    cls = 'json-boolean';
-                } else if (/null/.test(match)) {
-                    cls = 'json-null';
                 }
-                return '<span class="' + cls + '">' + match + '</span>';
+            }
+            
+            const isArray = Array.isArray(obj);
+            const entries = isArray ? obj.map((v, i) => [i, v]) : Object.entries(obj);
+            const isEmpty = entries.length === 0;
+            
+            if (isEmpty) {
+                return isArray ? 
+                    `<span class="json-bracket">[]</span>` : 
+                    `<span class="json-bracket">{}</span>`;
+            }
+            
+            const id = 'json-' + Math.random().toString(36).substr(2, 9);
+            const summary = isArray ? 
+                `<span class="json-summary">${entries.length} items</span>` :
+                `<span class="json-summary">${entries.length} keys</span>`;
+            
+            let html = `<div class="json-line">`;
+            for (let i = 0; i < level; i++) {
+                html += `<span class="json-indent"></span>`;
+            }
+            html += `<span class="json-toggle expanded" onclick="toggleJSON('${id}')"></span>`;
+            html += `<span class="json-bracket">${isArray ? '[' : '{'}</span>`;
+            html += summary;
+            html += `</div>`;
+            
+            html += `<div class="json-children" id="${id}">`;
+            
+            entries.forEach(([key, value], index) => {
+                const isLast = index === entries.length - 1;
+                const valueIsObject = value !== null && typeof value === 'object';
+                
+                html += `<div class="json-line">`;
+                for (let i = 0; i <= level; i++) {
+                    html += `<span class="json-indent"></span>`;
+                }
+                
+                if (!isArray) {
+                    html += `<span class="json-key">"${escapeHtml(key)}"</span>`;
+                    html += `<span class="json-separator">:</span>`;
+                }
+                
+                if (valueIsObject) {
+                    html += renderJSONTree(value, level + 1);
+                } else {
+                    if (typeof value === 'string') {
+                        const displayValue = value.length > 100 ? 
+                            escapeHtml(value.substr(0, 100)) + '...' : 
+                            escapeHtml(value);
+                        html += `<span class="json-string">"${displayValue}"</span>`;
+                        html += `<button class="json-copy-btn" onclick="copyValue('${escapeHtml(value).replace(/'/g, "\\'")}')">复制</button>`;
+                    } else if (typeof value === 'number') {
+                        html += `<span class="json-number">${value}</span>`;
+                    } else if (typeof value === 'boolean') {
+                        html += `<span class="json-boolean">${value}</span>`;
+                    } else if (value === null) {
+                        html += `<span class="json-null">null</span>`;
+                    }
+                }
+                
+                if (!isLast) {
+                    html += `<span class="json-separator">,</span>`;
+                }
+                
+                html += `</div>`;
+            });
+            
+            html += `</div>`;
+            
+            html += `<div class="json-line">`;
+            for (let i = 0; i < level; i++) {
+                html += `<span class="json-indent"></span>`;
+            }
+            html += `<span class="json-bracket">${isArray ? ']' : '}'}</span>`;
+            html += `</div>`;
+            
+            return html;
+        }
+
+        // HTML 转义
+        function escapeHtml(str) {
+            const div = document.createElement('div');
+            div.textContent = str;
+            return div.innerHTML;
+        }
+
+        // 切换折叠/展开
+        function toggleJSON(id) {
+            const element = document.getElementById(id);
+            const toggle = element.previousElementSibling.querySelector('.json-toggle');
+            
+            if (element.classList.contains('collapsed')) {
+                element.classList.remove('collapsed');
+                toggle.classList.remove('collapsed');
+                toggle.classList.add('expanded');
+            } else {
+                element.classList.add('collapsed');
+                toggle.classList.remove('expanded');
+                toggle.classList.add('collapsed');
+            }
+        }
+
+        // 复制单个值
+        function copyValue(value) {
+            navigator.clipboard.writeText(value).then(() => {
+                showToast('已复制');
+            }).catch(() => {
+                showToast('复制失败', 'error');
             });
         }
 
@@ -652,7 +843,7 @@
                     currentViewData = data;
                     
                     document.getElementById('view-modal-title').textContent = `查看数据 - ${tag}`;
-                    document.getElementById('json-content').innerHTML = syntaxHighlight(data);
+                    document.getElementById('json-content').innerHTML = renderJSONTree(data);
                     
                     openModal('view-modal');
                 } else {