Clarify missing player error for admins

src/analysis.ts

@@ -69,7 +69,9 @@ export function analysisRouter(db: SupabaseClient, secret: string, onCompleted?:
       if (!isAdmin) playerQuery = playerQuery.eq("user_id", userId);
       const { data: player, error: playerError } = await playerQuery.maybeSingle();
       if (playerError) return res.status(503).json({ error: "Unable to verify the selected player." });
-      if (!player) return res.status(404).json({ error: "Choose a player from your own roster before starting analysis." });
+      if (!player) return res.status(404).json({ error: isAdmin
+        ? "The selected player was not found. Refresh the player list and try again."
+        : "Choose a player from your own roster before starting analysis." });
       if (isAdmin) {
         const { error } = await db.rpc("admin_create_analysis_session", {
           p_session_id: input.clientId,