preview test send: keep {{ UnsubscribeURL }} (real link); hero 4-col to save vertical space

- send_test no longer overwrites {{ UnsubscribeURL }} with a dead static URL;
  Listmonk renders it into a working per-subscriber unsubscribe link.
- dot-compliance hero grid: 4 columns (minmax 150px, max-width 920px) instead
  of 3 to reduce vertical space.

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

scripts/build_trucking_campaigns.py

@@ -187,7 +187,9 @@ def send_test(base: dict, campaign_id: int, sample_row: tuple, label: str, tz: s
     body = body.replace("{{ .Subscriber.Attribs.company }}", name or "Sample Carrier LLC")
     body = body.replace("{{ .Subscriber.Attribs.dot_number }}", dot or "0000000")
     body = body.replace("{{ .Subscriber.Attribs.state }}", state or "TX")
-    body = body.replace("{{ UnsubscribeURL }}", "https://performancewest.net/unsubscribe")
+    # NOTE: leave {{ UnsubscribeURL }} alone — Listmonk renders it into a real,
+    # working per-subscriber unsubscribe link (even on test sends). Overwriting it
+    # produced a dead /unsubscribe link with no subscriber identity.
     subj = base["subject"].replace("{{ .Subscriber.Attribs.dot_number }}", dot or "0000000")
     # Listmonk /test needs `lists` as an array of IDs (base["lists"] is objects)
     list_ids = [l["id"] for l in base.get("lists", []) if isinstance(l, dict)] or [1]