```

feat(project): 添加项目数据导出功能

- 在项目查询界面添加导出按钮，支持将项目结果导出为CSV文件
- 实现exportProjectResults函数处理导出逻辑，包括参数验证和文件下载
- 新增validateProjectFilters函数用于验证项目筛选条件
- 新增buildProjectQueryParams函数构建查询参数
- 在服务端添加/api/projects/export接口，返回CSV格式数据
- 实现CSV文件生成和下载功能，包含中文文件名处理
- 重构项目查询逻辑，提取getProjects函数复用代码
```

public/index.html

@@ -622,6 +622,7 @@
                         <div style="display:flex;gap:10px;align-items:center;">
                             <button class="btn btn-primary btn-sm" onclick="searchProjectResults()">查询</button>
                             <button class="btn btn-secondary btn-sm" onclick="resetProjectFilters()">重置</button>
+                            <button class="btn btn-success btn-sm" id="btnExportProjects" onclick="exportProjectResults(this)">导出</button>
                             <!-- <button class="btn btn-danger btn-sm" onclick="clearResults()">清空全部</button> -->
                         </div>
                     </div>
@@ -1130,21 +1131,10 @@
 
         async function loadProjectResults() {
             try {
-                await loadProjectFilters();
-                const params = new URLSearchParams({ page: currentProjectsPage, pageSize: 10 });
                 const projectFilters = getProjectFilterValues();
-
-                if (projectFilters.minAmount && projectFilters.maxAmount && Number(projectFilters.minAmount) > Number(projectFilters.maxAmount)) {
-                    throw new Error('最小金额不能大于最大金额');
-                }
-
-                if (projectFilters.startDate && projectFilters.endDate && projectFilters.startDate > projectFilters.endDate) {
-                    throw new Error('开始日期不能晚于结束日期');
-                }
-
-                Object.entries(projectFilters).forEach(([key, value]) => {
-                    if (value !== '') params.set(key, value);
-                });
+                validateProjectFilters(projectFilters);
+                await loadProjectFilters();
+                const params = buildProjectQueryParams({ projectFilters, includePagination: true });
 
                 const res = await fetch('/api/projects?' + params);
                 const json = await res.json();
@@ -1198,6 +1188,31 @@
             };
         }
 
+        function validateProjectFilters(projectFilters) {
+            if (projectFilters.minAmount && projectFilters.maxAmount && Number(projectFilters.minAmount) > Number(projectFilters.maxAmount)) {
+                throw new Error('最小金额不能大于最大金额');
+            }
+
+            if (projectFilters.startDate && projectFilters.endDate && projectFilters.startDate > projectFilters.endDate) {
+                throw new Error('开始日期不能晚于结束日期');
+            }
+        }
+
+        function buildProjectQueryParams({ projectFilters = getProjectFilterValues(), includePagination = true } = {}) {
+            const params = new URLSearchParams();
+
+            if (includePagination) {
+                params.set('page', currentProjectsPage);
+                params.set('pageSize', 10);
+            }
+
+            Object.entries(projectFilters).forEach(([key, value]) => {
+                if (value !== '') params.set(key, value);
+            });
+
+            return params;
+        }
+
         function searchProjectResults() {
             currentProjectsPage = 1;
             loadProjectResults();
@@ -1220,6 +1235,73 @@
             loadProjectResults();
         }
 
+        async function exportProjectResults(buttonEl) {
+            const btn = buttonEl || document.getElementById('btnExportProjects');
+            const originalText = btn ? btn.textContent : '导出';
+
+            try {
+                const projectFilters = getProjectFilterValues();
+                validateProjectFilters(projectFilters);
+
+                if (btn) {
+                    btn.disabled = true;
+                    btn.textContent = '导出中...';
+                }
+
+                const res = await fetch('/api/projects/export?' + buildProjectQueryParams({
+                    projectFilters,
+                    includePagination: false,
+                }));
+
+                if (!res.ok) {
+                    let message = '导出失败';
+                    try {
+                        const json = await res.json();
+                        message = json.error || message;
+                    } catch (_error) {
+                        // Ignore JSON parse failure and use the fallback message.
+                    }
+                    throw new Error(message);
+                }
+
+                const blob = await res.blob();
+                const downloadUrl = URL.createObjectURL(blob);
+                const link = document.createElement('a');
+                link.href = downloadUrl;
+                link.download = getDownloadFilename(
+                    res.headers.get('content-disposition'),
+                    `projects-${new Date().toISOString().slice(0, 19).replace(/[-:]/g, '').replace('T', '-')}.csv`
+                );
+                document.body.appendChild(link);
+                link.click();
+                link.remove();
+                URL.revokeObjectURL(downloadUrl);
+            } catch (e) {
+                alert('导出失败: ' + e.message);
+            } finally {
+                if (btn) {
+                    btn.disabled = false;
+                    btn.textContent = originalText;
+                }
+            }
+        }
+
+        function getDownloadFilename(contentDisposition, fallbackName) {
+            if (!contentDisposition) return fallbackName;
+
+            const utf8Match = contentDisposition.match(/filename\*=UTF-8''([^;]+)/i);
+            if (utf8Match && utf8Match[1]) {
+                return decodeURIComponent(utf8Match[1]);
+            }
+
+            const asciiMatch = contentDisposition.match(/filename="([^"]+)"/i) || contentDisposition.match(/filename=([^;]+)/i);
+            if (asciiMatch && asciiMatch[1]) {
+                return asciiMatch[1].trim();
+            }
+
+            return fallbackName;
+        }
+
         function renderResults({ data, total, page, pageSize, listId, paginationId }) {
             const container = document.getElementById(listId);
             if (!data || data.length === 0) {