idz: Un-hardcode result limit in repo layer

Minor design nit but I should probably take my own code review
advice.

src/idz/handler/loadTopTen.ts

@@ -18,7 +18,7 @@ export async function loadTopTen(
     }
 
     const { routeNo, minTimestamp } = selector;
-    const src = await w.timeAttack().loadTopTen(routeNo, minTimestamp);
+    const src = await w.timeAttack().loadTop(routeNo, minTimestamp, 10);
 
     if (src.length === 0) {
       continue;

src/idz/repo.ts

@@ -116,9 +116,10 @@ export interface TopTenResult {
 }
 
 export interface TimeAttackRepository {
-  loadTopTen(
+  loadTop(
     routeNo: Model.RouteNo,
-    minTimestamp: Date
+    minTimestamp: Date,
+    limit: number
   ): Promise<TopTenResult[]>;
 
   loadAll(profileId: Id<Model.Profile>): Promise<Model.TimeAttackScore[]>;

src/idz/sql/timeAttack.ts

@@ -24,9 +24,10 @@ function _extractRow(row: Row): TimeAttackScore {
 export class SqlTimeAttackRepository implements TimeAttackRepository {
   constructor(private readonly _txn: Transaction) {}
 
-  async loadTopTen(
+  async loadTop(
     routeNo: RouteNo,
-    minTimestamp: Date
+    minTimestamp: Date,
+    limit: number
   ): Promise<TopTenResult[]> {
     // We're not using an ORM here so this join-heavy SQL is unfortunately
     // going to be a boilerplated mess.
@@ -55,7 +56,7 @@ export class SqlTimeAttackRepository implements TimeAttackRepository {
       .where("ta.route_no", routeNo)
       .where(sql.gt("ta.timestamp", minTimestamp))
       .orderBy(["ta.total_time asc", "ta.timestamp asc"])
-      .limit(10);
+      .limit(limit);
 
     const rows = await this._txn.fetchRows(loadSql);