Preserve health during empty-server monitoring handoff (Refs #148)

src/lib/server/fleet/beta-tests.ts

@@ -132,8 +132,22 @@ export async function observeRun(run: TestRun, plan: BetaPlan): Promise<void> {
     const m = readMetrics(run);
     const row = getServer(run.server);
     const server = row ? serverObservation(row) : null;
-    const timestamp =
+    let timestamp =
         server?.status_source === 'telemetry' ? server.last_seen_at : server?.last_checked_at;
+    let source = server?.status_source;
+    // Telemetry owns the displayed roster until it expires, but a newer
+    // successful RCON reply is already health evidence during the handoff.
+    const rconSeen = server?.rcon_status?.last_seen_at;
+    if (
+        server?.health === 'online' &&
+        server.status_source === 'telemetry' &&
+        rconSeen &&
+        Date.parse(rconSeen) > Date.parse(timestamp ?? '') &&
+        Date.parse(rconSeen) <= Date.now()
+    ) {
+        timestamp = rconSeen;
+        source = 'rcon';
+    }
     const sample = Date.parse(timestamp ?? '');
     const freshSample =
         Number.isFinite(sample) &&
@@ -149,7 +163,7 @@ export async function observeRun(run: TestRun, plan: BetaPlan): Promise<void> {
         evidence(run, `sample:${sample}`, 'status-sample', {
             healthy,
             checkedAt: timestamp,
-            source: server?.status_source
+            source
         });
     if (before !== m.wasHealthy)
         evidence(run, `health:${at}`, 'health', { healthy, reason: server?.last_error ?? null });