feat(gdelt-intel): tone/vol sparkline summary bar in GdeltIntelPanel (#2152)

* feat(gdelt-intel): add tone/vol sparkline summary bar to GdeltIntelPanel

Surfaces GDELT tone and volume timeline data (seeded by PR #2087) in the
existing intel panel. A compact summary bar appears between the topic tabs
and article list, showing:
- 14-day tone sparkline (red=negative, green=positive) + current value badge
- 14-day volume sparkline + last-point count
- Gracefully hidden when timeline data is unavailable

Changes:
- gdelt-intel.ts: add TopicTimeline type, fetchTopicTimeline() with 5-min
  client cache; reuses existing IntelligenceServiceClient
- GdeltIntelPanel.ts: fetch timeline in parallel with articles via
  Promise.all; renderTopicSummary() builds the bar using miniSparkline();
  cached timeline served immediately on tab switch
- main.css: .gdelt-topic-summary / .gdelt-trend-group / .gdelt-trend-value
  styles

* fix(gdelt-intel): add tone/vol sparkline info to panel ? tooltip (all 21 locales)

* fix(gdelt-intel): rename GDELT Intelligence → News Intelligence in panel tooltip (all 21 locales)

src/styles/main.css

@@ -12195,6 +12195,39 @@ a.prediction-link:hover {
   overflow: hidden;
 }
 
+.gdelt-topic-summary {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  padding: 6px 12px;
+  background: var(--surface);
+  border-bottom: 1px solid var(--border);
+  gap: 12px;
+  flex-wrap: wrap;
+}
+
+.gdelt-trend-group {
+  display: flex;
+  align-items: center;
+  gap: 5px;
+}
+
+.gdelt-trend-label {
+  font-size: 10px;
+  color: var(--text-dim);
+  text-transform: uppercase;
+  letter-spacing: 0.3px;
+}
+
+.gdelt-trend-value {
+  font-size: 11px;
+  font-weight: 600;
+  color: var(--text-dim);
+}
+
+.gdelt-trend-value.positive { color: var(--success); }
+.gdelt-trend-value.negative { color: var(--danger); }
+
 /* Hotspot GDELT Context */
 .hotspot-gdelt-context {
   margin-top: 12px;