fix(insights): suppress AI credentials warning during loading state

The warning was showing briefly on every page load because
`!aiConfigQuery.data?.configured` evaluated to true while the query
was still in-flight (data === undefined). Guard with `!isLoading` so
the amber box only appears after the query resolves with configured=false.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/web/src/components/analytics/InsightsPanel.tsx

@@ -243,7 +243,7 @@ export function InsightsPanel() {
           Project Narrative
         </h2>
 
-        {!aiConfigQuery.data?.configured ? (
+        {!aiConfigQuery.isLoading && !aiConfigQuery.data?.configured ? (
           <div className="rounded-xl border border-amber-200 bg-amber-50 p-4 dark:border-amber-900 dark:bg-amber-950/30">
             <p className="text-sm text-amber-800 dark:text-amber-300">
               AI is not configured.{" "}