♻️ Add constructor (#1845)

Author: KATO-Hiro

src/lib/stores/active_contest_type.svelte.ts

@@ -14,6 +14,16 @@ import { type ContestTableProviders } from '$lib/utils/contest_table_provider';
 export class ActiveContestTypeStore {
   value = $state<ContestTableProviders>('abcLatest20Rounds');
 
+  /**
+   * Creates an instance with the specified contest type.
+   *
+   * @param defaultContestType - The default contest type to initialize.
+   * Defaults to 'abcLatest20Rounds'.
+   */
+  constructor(defaultContestType: ContestTableProviders = 'abcLatest20Rounds') {
+    this.value = defaultContestType;
+  }
+
   /**
    * Gets the current contest table providers.
    *