feat(logs): add scenario run logs export

- Backend: logs export endpoint for CSV and Markdown formats
- Frontend: ExportLogsModal with download button on run detail page
- Updated i18n and CHANGELOG
- Version bump: 1.9.1 -> 1.10.0

client/src/api/client.ts

@@ -292,6 +292,9 @@ export const runs = {
     const qs = q?.trim() ? `?q=${encodeURIComponent(q.trim())}` : '';
     return request(`/scenarios/${scenarioId}/run/${runId}${qs}`);
   },
+  exportLogs(scenarioId: string, runId: string, format: 'csv' | 'md'): Promise<string> {
+    return request(`/scenarios/${scenarioId}/run/${runId}/logs/export?format=${format}`);
+  },
 };
 
 // ── Scenario Credentials ──────────────────────────────────────────────────────

client/src/components/modals/ExportLogsModal.module.css

@@ -0,0 +1,27 @@
+.section {
+  display: flex;
+  flex-direction: column;
+  gap: 0.5rem;
+}
+
+.sectionTitle {
+  font-size: 0.8125rem;
+  font-weight: 600;
+  color: var(--text-muted, #888);
+  margin: 0;
+  text-transform: uppercase;
+  letter-spacing: 0.04em;
+}
+
+.radioRow {
+  display: flex;
+  align-items: center;
+  gap: 0.5rem;
+  font-size: 0.875rem;
+  cursor: pointer;
+}
+
+.radioRow input[type='radio'] {
+  cursor: pointer;
+  accent-color: var(--color-primary);
+}

client/src/components/modals/ExportLogsModal.tsx

@@ -0,0 +1,68 @@
+import { useTranslation } from 'react-i18next';
+import { X, Download } from 'lucide-react';
+import { Modal, Button } from '../../ui';
+import styles from './ExportLogsModal.module.css';
+
+export type LogExportFormat = 'md' | 'csv';
+
+export interface ExportLogsModalProps {
+  open: boolean;
+  format: LogExportFormat;
+  onFormatChange: (format: LogExportFormat) => void;
+  onClose: () => void;
+  onExport: () => void;
+  isExporting: boolean;
+}
+
+export function ExportLogsModal({
+  open,
+  format,
+  onFormatChange,
+  onClose,
+  onExport,
+  isExporting,
+}: ExportLogsModalProps) {
+  const { t } = useTranslation();
+
+  return (
+    <Modal
+      open={open}
+      title={t('runs.export_logs_modal_title')}
+      onClose={() => !isExporting && onClose()}
+      footer={
+        <>
+          <Button variant="secondary" onClick={onClose} disabled={isExporting}>
+            <X size={14} />
+            {t('common.button_cancel')}
+          </Button>
+          <Button variant="primary" onClick={onExport} disabled={isExporting}>
+            <Download size={14} />
+            {t('runs.action_export')}
+          </Button>
+        </>
+      }
+    >
+      <div className={styles.section}>
+        <h4 className={styles.sectionTitle}>{t('runs.export_logs_format')}</h4>
+        <label className={styles.radioRow}>
+          <input
+            type="radio"
+            name="log-export-format"
+            checked={format === 'md'}
+            onChange={() => onFormatChange('md')}
+          />
+          <span>{t('runs.export_logs_format_md')}</span>
+        </label>
+        <label className={styles.radioRow}>
+          <input
+            type="radio"
+            name="log-export-format"
+            checked={format === 'csv'}
+            onChange={() => onFormatChange('csv')}
+          />
+          <span>{t('runs.export_logs_format_csv')}</span>
+        </label>
+      </div>
+    </Modal>
+  );
+}

client/src/components/modals/index.ts

@@ -4,3 +4,5 @@ export { ExportScenarioModal } from './ExportScenarioModal';
 export type { ExportScenarioModalProps } from './ExportScenarioModal';
 export { RunScenarioModal } from './RunScenarioModal';
 export type { RunScenarioModalProps } from './RunScenarioModal';
+export { ExportLogsModal } from './ExportLogsModal';
+export type { ExportLogsModalProps, LogExportFormat } from './ExportLogsModal';

client/src/i18n/locales/en.json

@@ -257,7 +257,13 @@
     "step_description": "Result",
     "log_level": "Level",
     "log_message": "Message",
-    "log_time": "Time"
+    "log_time": "Time",
+    "action_download_logs": "Download logs",
+    "export_logs_modal_title": "Export logs",
+    "export_logs_format": "Format",
+    "export_logs_format_md": "Markdown (.md)",
+    "export_logs_format_csv": "CSV (.csv)",
+    "action_export": "Export"
   },
   "snippets": {
     "title": "Snippets",

client/src/pages/run/RunDetailPage.tsx

@@ -14,6 +14,7 @@ import type {
   FileMetadata,
 } from '../../api';
 import { scenarios } from '../../api';
+import { ExportLogsModal, type LogExportFormat } from '../../components/modals';
 import {
   AutoRefreshIndicator,
   Badge,
@@ -84,6 +85,9 @@ export function RunDetailPage() {
   const [artifacts, setArtifacts] = useState<FileMetadata[]>([]);
   const [artifactsTotal, setArtifactsTotal] = useState(0);
   const [artifactsLoading, setArtifactsLoading] = useState(false);
+  const [exportLogsOpen, setExportLogsOpen] = useState(false);
+  const [exportLogsFormat, setExportLogsFormat] = useState<LogExportFormat>('md');
+  const [exportingLogs, setExportingLogs] = useState(false);
   const logSearchRef = useRef('');
   const LOG_PAGE_SIZE = 25;
   const pollRef = useRef<ReturnType<typeof setInterval> | null>(null);
@@ -106,6 +110,27 @@ export function RunDetailPage() {
   const isFileExpired = (file: FileMetadata) =>
     file.expiresAt != null && new Date(file.expiresAt).getTime() <= Date.now();
 
+  const handleExportLogs = async () => {
+    if (!id || !runId) return;
+    setExportingLogs(true);
+    try {
+      const content = await runs.exportLogs(id, runId, exportLogsFormat);
+      const mimeType = exportLogsFormat === 'csv' ? 'text/csv' : 'text/markdown';
+      const blob = new Blob([content], { type: mimeType });
+      const url = URL.createObjectURL(blob);
+      const a = document.createElement('a');
+      a.href = url;
+      a.download = `run-${runId}-logs.${exportLogsFormat}`;
+      a.click();
+      URL.revokeObjectURL(url);
+      setExportLogsOpen(false);
+    } catch {
+      // error toast is already emitted by the API client
+    } finally {
+      setExportingLogs(false);
+    }
+  };
+
   const manualRefresh = () => {
     if (!id || !runId) return;
     runs
@@ -436,11 +461,17 @@ export function RunDetailPage() {
             <div className={styles.stepsSection}>
               <div className={styles.sectionHeadingRow}>
                 <h2 className={styles.sectionHeading}>{t('runs.logs_heading')}</h2>
-                <Search
-                  value={logSearch}
-                  onChange={setLogSearch}
-                  placeholder={t('runs.logs_search_placeholder')}
-                />
+                <div style={{ display: 'flex', alignItems: 'center', gap: '8px' }}>
+                  <Search
+                    value={logSearch}
+                    onChange={setLogSearch}
+                    placeholder={t('runs.logs_search_placeholder')}
+                  />
+                  <Button variant="secondary" size="sm" onClick={() => setExportLogsOpen(true)}>
+                    <Download size={14} />
+                    {t('runs.action_download_logs')}
+                  </Button>
+                </div>
               </div>
               <Table
                 columns={logColumns}
@@ -523,6 +554,15 @@ export function RunDetailPage() {
           )}
         </>
       )}
+
+      <ExportLogsModal
+        open={exportLogsOpen}
+        format={exportLogsFormat}
+        onFormatChange={setExportLogsFormat}
+        onClose={() => setExportLogsOpen(false)}
+        onExport={handleExportLogs}
+        isExporting={exportingLogs}
+      />
     </div>
   );
 }