feat(web): summarization-mode UI — all-videos list, Summarize queue, mode toggle

The list now shows ALL videos (ListVideos), not just summaries. Summarized cards
are unchanged; discovered-but-unsummarized videos render with a muted "pending"
treatment and either a "Summarize" button or a "Queued" chip.

- POST /v/{videoId}/summarize queues a video (RequestSummarize) and returns the
  refreshed card — it does NOT run the engine inline; `tapir run` is the single
  summarization driver, which picks up the flag on its next pass.
- Account page gains an Automatic/Manual toggle (POST /account/summarize-mode →
  SetAutoSummarize), shown as the current mode with a one-click switch.
- Both new POSTs degrade without JS (redirect back); HTMX swaps the fragment.

VideoCard and summarizeModeControl are extracted templ fragments reused as the
HTMX swap targets. views_templ.go regenerated.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

internal/web/handlers_test.go

@@ -185,8 +185,10 @@ func TestListRendersRowsAndActionState(t *testing.T) {
 func TestListHTMXReturnsFragment(t *testing.T) {
 	ctx := context.Background()
 	app := newApp(t)
-	resetDB(t, rawPool(t))
+	p := rawPool(t)
+	resetDB(t, p)
 	require.NoError(t, deliver(ctx, app, videoX, "body x"))
+	seedVideo(t, p, videoX, "X Title", "https://x", time.Time{})
 
 	req := httptest.NewRequest(http.MethodGet, "/", nil)
 	req.Header.Set("HX-Request", "true")
@@ -290,6 +292,103 @@ func TestActionRejectsUnknownVerb(t *testing.T) {
 	require.Equal(t, http.StatusBadRequest, rec.Code)
 }
 
+func TestListShowsSummarizeButtonForUnsummarized(t *testing.T) {
+	app := newApp(t)
+	p := rawPool(t)
+	resetDB(t, p)
+	// A discovered-but-unsummarized video (no summary delivered).
+	seedVideo(t, p, videoX, "Pending Title", "https://x", time.Time{})
+
+	rec := do(t, app, httptest.NewRequest(http.MethodGet, "/", nil))
+	require.Equal(t, http.StatusOK, rec.Code)
+	html := body(t, rec)
+
+	require.Contains(t, html, "Pending Title", "unsummarized videos are listed too")
+	require.Contains(t, html, "Summarize", "a Summarize button is offered")
+	require.Contains(t, html, "/v/"+videoX+"/summarize", "button posts to the queue endpoint")
+	require.Contains(t, html, "card-pending", "muted pending treatment")
+	require.NotContains(t, html, "Queued", "not queued yet")
+}
+
+func TestRequestSummarizeQueuesAndRendersCard(t *testing.T) {
+	ctx := context.Background()
+	app := newApp(t)
+	p := rawPool(t)
+	resetDB(t, p)
+	seedVideo(t, p, videoX, "Pending Title", "https://x", time.Time{})
+
+	rec := postSummarize(t, app, videoX, true)
+	require.Equal(t, http.StatusOK, rec.Code)
+	html := body(t, rec)
+	require.Contains(t, html, "Queued", "card now shows the queued state")
+	require.NotContains(t, html, ">Summarize<", "the Summarize button is gone once queued")
+
+	// The flag is persisted, so the next run picks it up.
+	row, err := app.Store.GetVideoRow(ctx, userID, videoX)
+	require.NoError(t, err)
+	require.True(t, row.SummarizeRequested)
+}
+
+func TestRequestSummarizeNonHTMXRedirects(t *testing.T) {
+	ctx := context.Background()
+	app := newApp(t)
+	p := rawPool(t)
+	resetDB(t, p)
+	seedVideo(t, p, videoX, "Pending Title", "https://x", time.Time{})
+
+	rec := postSummarize(t, app, videoX, false)
+	require.Equal(t, http.StatusSeeOther, rec.Code)
+	require.Equal(t, "/", rec.Header().Get("Location"))
+
+	row, err := app.Store.GetVideoRow(ctx, userID, videoX)
+	require.NoError(t, err)
+	require.True(t, row.SummarizeRequested, "queued on the no-JS path too")
+}
+
+func TestRequestSummarizeNotFound(t *testing.T) {
+	app := newApp(t)
+	resetDB(t, rawPool(t))
+	rec := postSummarize(t, app, videoX, true)
+	require.Equal(t, http.StatusNotFound, rec.Code, "queuing an unknown video is a 404")
+}
+
+func TestSummarizeModeToggle(t *testing.T) {
+	ctx := context.Background()
+	app := newApp(t)
+	resetDB(t, rawPool(t))
+
+	// Account page defaults to manual.
+	rec := do(t, app, httptest.NewRequest(http.MethodGet, "/account", nil))
+	require.Equal(t, http.StatusOK, rec.Code)
+	html := body(t, rec)
+	require.Contains(t, html, "Manual", "default mode shown")
+	require.Contains(t, html, "Switch to automatic")
+
+	// Toggle to automatic via HTMX returns the refreshed control.
+	req := httptest.NewRequest(http.MethodPost, "/account/summarize-mode",
+		strings.NewReader("enabled=true"))
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	req.Header.Set("HX-Request", "true")
+	rec = do(t, app, req)
+	require.Equal(t, http.StatusOK, rec.Code)
+	html = body(t, rec)
+	require.Contains(t, html, "Automatic")
+	require.Contains(t, html, "Switch to manual")
+
+	got, err := app.Store.GetAutoSummarize(ctx, userID)
+	require.NoError(t, err)
+	require.True(t, got, "mode persisted")
+}
+
+func postSummarize(t *testing.T, app *web.App, videoID string, htmx bool) *httptest.ResponseRecorder {
+	t.Helper()
+	req := httptest.NewRequest(http.MethodPost, "/v/"+videoID+"/summarize", nil)
+	if htmx {
+		req.Header.Set("HX-Request", "true")
+	}
+	return do(t, app, req)
+}
+
 // deliver stores a summary through the App's store under test.
 func deliver(ctx context.Context, app *web.App, videoID, text string) error {
 	return app.Store.(*store.Store).Deliver(ctx, summary(videoID, text))