feat(crawler): honour CRAWLER_LIMIT in the in-process daemon (0.47.0)

The CLI binary already capped runs at CRAWLER_LIMIT mangas, but the
daemon's RealMetadataPass passed a hardcoded `0` (no cap) to
`pipeline::run_metadata_pass`, so the env var was silently ignored once
the daemon took over the metadata pass.

Adds `manga_limit` to `CrawlerConfig`, reads it from `CRAWLER_LIMIT`
(default 0 = no cap), and threads it through `RealMetadataPass::run`
so a daemon-driven sweep stops at the same boundary as a CLI run.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/package.json

@@ -1,6 +1,6 @@
 {
   "name": "mangalord-frontend",
-  "version": "0.46.0",
+  "version": "0.47.0",
   "private": true,
   "type": "module",
   "scripts": {