add ECB Data Portal source; group-aware stale thresholds

ECB Statistical Data Warehouse joins as a 5th data source — open API,
no key, daily euro-area yield curve data. Symbol format
'ECB:dataset/series_key', e.g. 'ECB:YC/B.U2.EUR.4F.G_N_A.SV_C_YM.SR_10Y'
for daily 10y AAA spot rate.

Bonds tab adds ECB EZ 10y AAA + 2y AAA so there's at least some
currently-fresh European sovereign data alongside the US Treasuries.
Country-specific yields (Bund/OAT/BTP/Gilt/JGB) remain on Eurostat/FRED
monthly mirrors — no free daily source exists for those.

Stale threshold is now per-group instead of a flat 90 days. Daily-tape
groups (bonds, rates, equity, etc.) flag stale after a week or three;
monthly groups (economy, macro, valuation) stay at 60-90 days. The
bonds tab will now correctly show 30-60 day-old country yields as
stale next to the daily US/ECB ones.

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

app/routers/api.py

@@ -55,6 +55,25 @@ router = APIRouter(dependencies=[Depends(require_token)])
 JOB_NAMES = ("market_job", "news_job", "portfolio_job", "ai_log_job", "rollup_job")
 JOB_STALE_HOURS = 2.0  # job is "warn" if its last success was >2h ago
 
+# Per-group expected freshness — bonds and intraday tape want daily data,
+# macro/economy/valuation are monthly/quarterly by nature. Older than this
+# many days from today → row gets a "stale" badge.
+_STALE_DAYS_BY_GROUP = {
+    "bonds":       21,
+    "rates":       7,
+    "equity":      7,
+    "mag7":        7,
+    "commodities": 7,
+    "fx":          7,
+    "tech_ai":     7,
+    "financials":  7,
+    "bubble_watch":21,
+    "valuation":   60,
+    "macro":       60,
+    "economy":     90,
+}
+_STALE_DAYS_DEFAULT = 90
+
 
 # --- Small helpers -----------------------------------------------------------
 
@@ -158,17 +177,18 @@ async def indicators(
             .limit(1)
         )).scalar_one_or_none()
 
-        # Mark rows whose `as_of` is older than 90 days as stale so the UI
-        # can dim them — some FRED international series are months/years
-        # behind their primary source.
+        # Mark rows whose `as_of` is older than the group-specific threshold.
+        # Daily-tape groups (bonds, rates, equity, ...) flag stale earlier
+        # than monthly groups (economy, macro, valuation).
         today = utcnow().date()
+        threshold = _STALE_DAYS_BY_GROUP.get(group, _STALE_DAYS_DEFAULT)
         stale_symbols: set[str] = set()
         for r in rows:
             try:
                 as_of_d = datetime.strptime(r.as_of, "%Y-%m-%d").date() if r.as_of else None
             except ValueError:
                 as_of_d = None
-            if as_of_d and (today - as_of_d).days > 90:
+            if as_of_d and (today - as_of_d).days > threshold:
                 stale_symbols.add(r.symbol)
 
         return templates.TemplateResponse(