feat(admin): observability — job history, live "now analyzing", durations & metrics

Crawler + analysis admin dashboards gain a Live / History / Metrics
segmented view.

History: searchable, filterable, paginated job log per subsystem
(crawler_jobs across all states/kinds; page_analysis terminal outcomes),
with inline dead-job requeue and a Duration column.

Live: enrich analysis SSE events with manga title + chapter number and add
a sticky "Now analyzing" banner that jumps to and highlights the page.

Metrics: new durable crawl_metrics table (migration 0028) timing every
crawl op (manga list walk, manga detail, cover, whole chapter; per-page
derived from chapter) plus page_analysis.duration_ms for analysis. New
endpoints serve per-type average durations + success rates and a recent-ops
log; a cron reaper (CRAWL_METRICS_RETENTION_DAYS) bounds growth.

Tested: repo + API integration tests, vitest for the API client and
fmtDuration, and Playwright for the History/Metrics tabs.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/e2e/admin-analysis.spec.ts

@@ -155,6 +155,48 @@ async function mockAdmin(page: Page, cap: Captured) {
         })
     );
 
+    // Analysis history (terminal-outcome log). Registered before the
+    // page-detail routes are matched by their more-specific globs.
+    await page.route('**/api/v1/admin/analysis/history**', (r) =>
+        r.fulfill({
+            status: 200,
+            contentType: 'application/json',
+            body: JSON.stringify({
+                items: [
+                    {
+                        page_id: pageDone,
+                        page_number: 1,
+                        chapter_id: chapterId,
+                        chapter_number: 1,
+                        manga_id: mangaId,
+                        manga_title: 'Berserk',
+                        status: 'done',
+                        is_nsfw: true,
+                        model: 'test-model',
+                        error: null,
+                        analyzed_at: '2026-06-13T12:00:00Z',
+                        duration_ms: 2400
+                    }
+                ],
+                page: { limit: 25, offset: 0, total: 1 }
+            })
+        })
+    );
+
+    await page.route('**/api/v1/admin/analysis/metrics**', (r) =>
+        r.fulfill({
+            status: 200,
+            contentType: 'application/json',
+            body: JSON.stringify({
+                n: 3204,
+                ok: 3159,
+                failed: 45,
+                avg_ms: 2400,
+                by_model: [{ model: 'qwen2-vl-7b', avg_ms: 2400, n: 3100 }]
+            })
+        })
+    );
+
     // Default: keep the SSE connection pending (no events) so tests that
     // don't care about live updates don't trigger reconnect churn. The
     // live-updates test overrides this with a fulfilling stream.
@@ -240,14 +282,18 @@ test.describe('/admin/analysis', () => {
                 kind: 'started',
                 page_id: pageNone,
                 manga_id: mangaId,
+                manga_title: 'Berserk',
                 chapter_id: chapterId,
+                chapter_number: 1,
                 page_number: 2
             })}\n\n` +
             `event: analysis\ndata: ${JSON.stringify({
                 kind: 'completed',
                 page_id: pageNone,
                 manga_id: mangaId,
+                manga_title: 'Berserk',
                 chapter_id: chapterId,
+                chapter_number: 1,
                 page_number: 2
             })}\n\n`;
         let served = false;
@@ -268,10 +314,81 @@ test.describe('/admin/analysis', () => {
         // (The mocked stream closes after its body, so the live pill flips
         // back to "Reconnecting…" — the ticker is the durable signal.)
         const tick = page.getByTestId('admin-analysis-ticker');
-        await expect(tick).toContainText('Analyzing page 2');
+        await expect(tick).toContainText('Analyzing Berserk');
         await expect(tick).toContainText('Analyzed page 2');
     });
 
+    test('now-analyzing banner appears from SSE and Jump expands the chapter', async ({
+        page
+    }) => {
+        const cap: Captured = { reenqueue: null, analyzeCalls: 0 };
+        await mockAdmin(page, cap);
+        // A single `started` frame, then hang so the banner stays put.
+        const frame = `event: analysis\ndata: ${JSON.stringify({
+            kind: 'started',
+            page_id: pageDone,
+            manga_id: mangaId,
+            manga_title: 'Berserk',
+            chapter_id: chapterId,
+            chapter_number: 1,
+            page_number: 1
+        })}\n\n`;
+        let served = false;
+        await page.route('**/api/v1/admin/analysis/status/stream', (r) => {
+            if (served) return new Promise(() => {});
+            served = true;
+            return r.fulfill({
+                status: 200,
+                headers: { 'content-type': 'text/event-stream' },
+                body: frame
+            });
+        });
+
+        await page.setViewportSize(DESKTOP);
+        await page.goto('/admin/analysis');
+
+        const banner = page.getByTestId('admin-analysis-now');
+        await expect(banner).toContainText('Now analyzing');
+        await expect(banner).toContainText('Berserk · Ch 1 · Page 1');
+
+        // Jump expands the manga + chapter and the analyzing chip appears.
+        await page.getByTestId('admin-analysis-now-jump').click();
+        await expect(page.getByTestId(`admin-analysis-page-${pageDone}`)).toBeVisible();
+    });
+
+    test('history tab lists terminal analyses and opens the detail modal', async ({
+        page
+    }) => {
+        const cap: Captured = { reenqueue: null, analyzeCalls: 0 };
+        await mockAdmin(page, cap);
+        await page.setViewportSize(DESKTOP);
+        await page.goto('/admin/analysis');
+
+        await page.getByTestId('admin-analysis-tab-history').click();
+        const row = page.getByTestId(`analysis-history-row-${pageDone}`);
+        await expect(row).toContainText('Berserk · Ch 1 · p1');
+        await expect(row).toContainText('NSFW');
+        await expect(row).toContainText('2.4s'); // duration column
+
+        await row.click();
+        await expect(page.getByTestId('admin-analysis-detail')).toBeVisible();
+        await expect(page.getByTestId('admin-analysis-detail-status')).toContainText(
+            'Analyzed'
+        );
+    });
+
+    test('metrics tab shows aggregate timing + by-model', async ({ page }) => {
+        const cap: Captured = { reenqueue: null, analyzeCalls: 0 };
+        await mockAdmin(page, cap);
+        await page.setViewportSize(DESKTOP);
+        await page.goto('/admin/analysis');
+
+        await page.getByTestId('admin-analysis-tab-metrics').click();
+        await expect(page.getByTestId('analysis-metrics-n')).toContainText('3204');
+        await expect(page.getByTestId('analysis-metrics-avg')).toContainText('2.4s');
+        await expect(page.getByTestId('analysis-metrics')).toContainText('qwen2-vl-7b');
+    });
+
     test('queue an unanalyzed page from its detail modal', async ({ page }) => {
         const cap: Captured = { reenqueue: null, analyzeCalls: 0 };
         await mockAdmin(page, cap);