feat(worker): claim_next skips per-item paused jobs

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

worker/tests/test_claim.py

@@ -24,3 +24,17 @@ def test_claim_does_not_repick_claimed_job(conn):
     insert_request(conn)
     assert claim_next(conn) is not None
     assert claim_next(conn) is None
+
+
+def test_claim_skips_paused_jobs(conn):
+    paused_job = insert_request(conn, album="Paused Album")
+    with conn.cursor() as cur:
+        cur.execute('UPDATE "Job" SET paused = true WHERE id = %s', (paused_job,))
+    conn.commit()
+    unpaused_job = insert_request(conn, album="Live Album")
+
+    claimed = claim_next(conn)
+    assert claimed == unpaused_job  # the paused one is skipped
+
+    # With only the paused job left, nothing is claimable.
+    assert claim_next(conn) is None