perf(scraper): use direct HTTP for chapter text fetching, bypass Browserless

novelfire.net chapter content is server-rendered, so Browserless is not
needed. Add a dedicated chapterClient (always StrategyDirect) to Scraper
and use it in ScrapeChapterText, removing the now-irrelevant WaitFor /
RejectResourceTypes / GotoOptions fields from the ContentRequest.

scraper/internal/storage/scrape_integration_test.go

@@ -57,7 +57,7 @@ func newScrapeAndStoreFixture(t *testing.T) (*novelfire.Scraper, *HybridStore) {
 		MaxConcurrent: 1,
 	})
 	log := slog.New(slog.NewTextHandler(os.Stderr, &slog.HandlerOptions{Level: slog.LevelWarn}))
-	sc := novelfire.New(client, log, client, nil)
+	sc := novelfire.New(client, log, client, nil, nil)
 	hs := newTestHybridStore(t)
 	return sc, hs
 }