feat(explore): Update confidence footer again (#103680)

This update follows a few philosophies:
1. use the number matched, number scanned, number total to inform the
user
2. give as much information to the user as possible about what was done
to compute the results
3. never display the same number more than once as it is
repetitive/redundant

<table>
<tr>
 <td>Spans
<td><img width="2730" height="2619" alt="image"
src="https://github.com/user-attachments/assets/858e47f7-b890-408a-8fe6-c044e075144a"
/>
<tr>
 <td>Logs
<td><img width="2423" height="1625" alt="image"
src="https://github.com/user-attachments/assets/a2ee6e1a-3ae8-42f9-bcf6-4a99986060d1"
/>
</table>

Author: Zylphrex

static/app/views/alerts/rules/metric/utils/determineSeriesSampleCount.tsx

@@ -44,7 +44,7 @@ export function determineSeriesSampleCountAndIsSampled(
       }
 
       const sampleRate = data[i]!.values[j]!.sampleRate;
-      if (sampleRate === 1) {
+      if (defined(sampleRate) && sampleRate >= 1) {
         hasUnsampledInterval = true;
       } else if (defined(sampleRate) && sampleRate < 1) {
         hasSampledInterval = true;