fix: make intake dedupe cutoff-aware so monitor upgrade path works end-to-end

The monitor's quality-upgrade path was inert: run_pipeline's intake
short-circuit treated any existing LibraryItem as "done", so a
monitor-driven upgrade job for a below-cutoff copy jumped straight to
imported without downloading. Intake now checks whether the job is
monitor-driven (Request.monitoredReleaseId IS NOT NULL) and, if so,
only short-circuits when the existing copy already meets the quality
cutoff; plain manual requests keep exact slice-1 behavior. Also drops
an unused `field` import in browser.py.

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

worker/lyra_worker/main.py

@@ -37,7 +37,8 @@ def run_forever() -> None:
                 time.sleep(IDLE_SLEEP)
                 continue
             print(f"worker: claimed job {job_id}", flush=True)
-            run_pipeline(conn, job_id, adapters, resolver=resolver, tagger=tagger)
+            run_pipeline(conn, job_id, adapters, resolver=resolver, tagger=tagger,
+                         upgrade_cutoff=mcfg.quality_cutoff)
             if mcfg.enabled:
                 try:
                     reconcile(conn, job_id, mcfg)