CourseRegistrationRepositoryのエラーハンドリングでError型もcatchするよう修正

[devin-ai-integration]

案件: Crashlytics Issue 81acd654738b8d5208a131903420f4f8

やったこと

• CourseRegistrationRepositoryImpl の全メソッド (getCourseRegistrations, registerCourse, unregisterCourse) に、Dart の Error 型（TypeError, BuiltValueNullFieldError 等）もキャッチして DomainError に変換する catch 句を追加

確認したこと

• 既存の on DomainError { rethrow; } → on Exception catch の流れは変更なし
• Exception を継承しない Error 型が発生した場合も DomainError(type: unknown) に変換されることを確認

メモ

• Firebase Crashlytics で CourseRegistrationRepositoryImpl.getCourseRegistrations の fatal issue が検出された
• 原因: on Exception catch は Dart の Error 型（TypeError, BuiltValueNullFieldError 等）をキャッチしない。APIレスポンスのマッピング中に Error が発生した場合、キャッチされずに PlatformDispatcher.instance.onError まで伝播し、fatal: true で Crashlytics に報告されていた
• 修正: 各メソッドに catch (e, stackTrace) 句を追加し、Error 型も DomainError に変換してから throw するようにした

Link to Devin session: https://app.devin.ai/sessions/cff41c8980ce479bb7d41f46eac5d536
Requested by: @kantacky

[devin-ai-integration]

Original prompt from Kanta

SYSTEM:
=== BEGIN THREAD HISTORY (in #dotto_noti_firebase) ===
Unknown User (B09U62J7Y9M): Heads up! We detected a new fatal issue in Dotto!

Heads up! We detected a new fatal issue in Dotto! Issue 81acd654738b8d5208a131903420f4f8: package:dotto/repository/course_registration_repository.dart - CourseRegistrationRepositoryImpl.getCourseRegistrations

<most_recent_message>
Kanta Oikawa (U071TQ4TLTB): @Devin
これは何のエラー？
</most_recent_message>
=== END THREAD HISTORY ===

Thread URL: https://furarico.slack.com/archives/C09UMBBKCRG/p1779244509896679?thread_ts=1779244509.896679&amp;cid=C09UMBBKCRG

The latest message is the one right above that tagged you. The <most_recent_message> is the message that you should use to guide your goals + task for this session, and you should use the rest of the slack thread as context.

[devin-ai-integration]

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