feat(e2e): use direct HTTP for chapter scraping, cap TTS at 200 chars

- e2e fixture: replace single contentClient with directClient (plain HTTP)
  for chapter/metadata/ranking + contentClient (Browserless) for urlClient
  only — matches production wiring and is significantly faster
- server: add max_chars field to audio request body; truncates stripped text
  to N runes before sending to Kokoro (used by e2e for quick TTS tests)
- fix: move RankingItem to scraper package to break novelfire→storage import
  cycle; storage.RankingItem is now a type alias for backward compat
- fix: update stale New() call in novelfire integration test (missing args)
- fix: replace removed blob-ranking methods in storage integration test with
  current per-item API (UpsertRankingItem/ListRankingItems/RankingLastUpdated)
- justfile: add test-e2e and e2e tasks

justfile

@@ -34,6 +34,25 @@ test-all: test test-integration
 test-pkg pkg:
     cd {{scraper_dir}} && go test -v -tags integration -timeout 600s ./{{pkg}}/...
 
+# Run end-to-end tests against live services.
+# All services must be running first (docker compose up -d or just e2e-up).
+# Override env vars as needed, e.g.:
+#   just test-e2e SCRAPER_URL=http://localhost:8080 KOKORO_VOICE=af_bella
+test-e2e \
+    browserless_url="http://localhost:3030" \
+    minio_endpoint="localhost:9000" \
+    pocketbase_url="http://localhost:8090" \
+    scraper_url="http://localhost:8080":
+    cd {{scraper_dir}} && \
+        BROWSERLESS_URL={{browserless_url}} \
+        MINIO_ENDPOINT={{minio_endpoint}} \
+        POCKETBASE_URL={{pocketbase_url}} \
+        SCRAPER_URL={{scraper_url}} \
+        go test -v -tags integration -timeout 900s ./internal/e2e/...
+
+# Start all services required for e2e tests, then run them
+e2e: up test-e2e
+
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