Dashboard: fix freshness-chip timezone bug + sync-aware thresholds

Live verification caught it: the data-freshness chip read ~14,477s (RED) on data
that was actually 1s fresh — exactly the EDT offset. Event timestamps are stored
NAIVE LOCAL (datetime.now()), but query_risk_state compared them against UTC now.
Compare naive-local to naive-local instead (tz-aware timestamps still use UTC).
Verified live: chip now reads ~78s. Also align the amber/red thresholds to the
~60s broker-sync cadence (amber >90s, red >180s) so a healthy feed reads green.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

api/static/dashboard.html

@@ -471,7 +471,8 @@ function render(d) {
   $("risk-day").textContent = rk.day_pnl_pct != null ? (rk.day_pnl_pct * 100).toFixed(1) + "% / -" + (rk.daily_loss_limit_pct * 100).toFixed(0) + "%" : "—";
   const fr = $("risk-fresh");
   fr.textContent = rk.data_age_s != null ? rk.data_age_s.toFixed(0) + "s" : "—";
-  fr.style.color = (rk.data_age_s == null) ? "" : (rk.data_age_s > 90 ? "#ff4d4f" : rk.data_age_s > 30 ? "#f1c40f" : "");
+  // broker sync runs ~every 60s, so >90s = a missed sync (amber), >180s = stale (red)
+  fr.style.color = (rk.data_age_s == null) ? "" : (rk.data_age_s > 180 ? "#ff4d4f" : rk.data_age_s > 90 ? "#f1c40f" : "");
 
   const accts = d.accounts || [];
   $("acct-count").textContent = accts.length;

storage/projections.py

@@ -625,8 +625,12 @@ def query_risk_state(store) -> dict:
             t = (datetime.fromisoformat(ts_latest.replace("Z", "+00:00"))
                  if isinstance(ts_latest, str) else ts_latest)
             if t.tzinfo is None:
-                t = t.replace(tzinfo=timezone.utc)
-            age = (datetime.now(timezone.utc) - t).total_seconds()
+                # event timestamps are stored NAIVE LOCAL (datetime.now()), so
+                # compare against naive-local now — comparing to UTC would be off
+                # by the whole timezone offset (the chip read ~4h on fresh data).
+                age = (datetime.now() - t).total_seconds()
+            else:
+                age = (datetime.now(timezone.utc) - t).total_seconds()
         except Exception:  # noqa: BLE001
             pass