fix(firms): drop the decimal when fire power rounds to 10 MW

A 9.96 MW detection was labeled 10.0 MW because the one-decimal cutoff ran before rounding.

src/data/firmsCards.test.mjs

@@ -53,6 +53,21 @@ test('buildFireCard: missing acquisition time omits the age segment', () => {
   assert.equal(card.details[0], 'high · N20');
 });
 
+test('buildFireCard: power that rounds to 10 MW drops the decimal', () => {
+  const crossed = buildFireCard(
+    { fire: fire({ frp: 9.96 }), position: {} },
+    NOW,
+  );
+  assert.equal(crossed.title, '▲ 10 MW');
+  const below = buildFireCard(
+    { fire: fire({ frp: 9.94 }), position: {} },
+    NOW,
+  );
+  assert.equal(below.title, '▲ 9.9 MW');
+  const selected = buildSelectedFireCard(fire({ frp: 9.96 }), NOW);
+  assert.equal(selected.title, 'FIRE · 10 MW');
+});
+
 test('buildFireCard: SNPP satellite code renders as SNPP, weak fire is not red', () => {
   const card = buildFireCard({ fire: fire({ satellite: 'N', frp: 0.8, confidence: 0.3 }), position: {} }, NOW);
   assert.match(card.details[0], /SNPP$/);