refactor(frontend): migrate Analysis.tsx to the banner system

frontend/src/pages/Analysis.tsx

@@ -1,5 +1,6 @@
 import { useEffect, useState } from "react";
 import { api } from "../api/client";
+import { showError } from "../banner";
 import { ProgressionChart } from "../components/charts/ProgressionChart";
 import type { ProgressionMetric, ProgressionPoint, WorkoutKind } from "../types/api";
 
@@ -18,7 +19,6 @@ export function Analysis() {
   const [metric, setMetric] = useState<ProgressionMetric>("pace");
   const [points, setPoints] = useState<ProgressionPoint[]>([]);
   const [loading, setLoading] = useState(false);
-  const [error, setError] = useState<string | null>(null);
 
   useEffect(() => {
     api
@@ -27,17 +27,16 @@ export function Analysis() {
         setKinds(k);
         if (k.length > 0) setSelectedKindId(k[0].ID);
       })
-      .catch((e) => setError(String(e)));
+      .catch((e) => showError(String(e)));
   }, []);
 
   useEffect(() => {
     if (selectedKindId == null) return;
     setLoading(true);
-    setError(null);
     api
       .progression(selectedKindId, metric)
       .then(setPoints)
-      .catch((e) => setError(String(e)))
+      .catch((e) => showError(String(e)))
       .finally(() => setLoading(false));
   }, [selectedKindId, metric]);
 
@@ -77,7 +76,6 @@ export function Analysis() {
             </label>
           </div>
 
-          {error && <p className="error">{error}</p>}
           {loading ? <p>Loading...</p> : <ProgressionChart points={points} metric={metric} />}
         </>
       )}