fix: rename variable to avoid shadowing expectedRounds function

Variable 'expectedRounds' was shadowing the imported function of the same name, causing TypeScript build failure.

src/app/api/tournaments/[id]/schedule/route.ts

@@ -175,8 +175,8 @@ export async function POST(_request: Request, { params }: RouteParams) {
     }
 
     // Calculate expected rounds
-    const expectedRounds = expectedRounds(teamCount);
-    console.log(`[Schedule API] Expected rounds: ${expectedRounds}`);
+    const numRounds = expectedRounds(teamCount);
+    console.log(`[Schedule API] Expected rounds: ${numRounds}`);
 
     if (teamDurability === "permanent") {
       // ============================================
@@ -285,7 +285,7 @@ export async function POST(_request: Request, { params }: RouteParams) {
       const schedule = generateVariableRoundRobin(
         participants,
         teamCount,
-        expectedRounds,
+        numRounds,
         generateTeamWithRotation
       );