Unify page routing and harden acquire wiring after review (#62)

backend/internal/latest/acquire_test.go

@@ -382,6 +382,30 @@ func TestAcquireKaganeSkippedWithoutBrowser(t *testing.T) {
 	}
 }
 
+// The byte half of "nothing falls back to a plain fetch": with a browser for
+// the page but none for the bytes, a kagane Cover stays absent and the TLS
+// cover fetcher is never consulted.
+func TestAcquireKaganeBytesNeverFallBackToPlainTLS(t *testing.T) {
+	s, _ := newTestStore(t)
+	browserPage := &fakeFetcher{body: kaganeSeriesAndCoverFixture, status: 200}
+	tlsCovers := &fakeBytesCoverFetcher{body: []byte("cover-bytes"), contentType: "image/webp"}
+	acq := &Acquirer{
+		Store: s, Fetch: &fakeFetcher{body: "", status: 403},
+		BrowserFetch: browserPage, Covers: tlsCovers,
+	}
+	s.OnSeriesCreated = acq.Acquire
+
+	bookmarkNewKaganeSeries(t, s)
+	acq.Wait()
+
+	if got := tlsCovers.callCount(); got != 0 {
+		t.Fatalf("plain-TLS cover fetches = %d, want 0 — kagane bytes are browser-only", got)
+	}
+	if got := readBookmark(t, s, kaganeKey); got.Cover != "" {
+		t.Fatalf("Cover = %q, want empty without a browser cover fetcher", got.Cover)
+	}
+}
+
 // novelfull's no-browser degradation differs from kagane's: only its HTML
 // needs the sidecar, so when the page body is available — the challenge is a
 // live time-varying fact that sometimes answers a plain request — the Cover