fix(task-results): skip getAnswers full-scan for anonymous users

[KATO-Hiro]

getAnswers(undefined) drops the WHERE filter and full-scans taskAnswer. Guard the call in createTaskResults / getTaskResultsOnlyResultExists so anonymous users skip the DB round-trip, and make userId types honest (string | undefined), including TaskResult.user_id.

Summary by CodeRabbit

リリースノート

• 新機能

  • ログインなし（未ログイン）の状態でも、タスク結果の取得・表示が可能になりました。
  • タグ条件でのタスク結果取得にも対応し、未挑戦のタスクはデフォルト表示されます。

• テスト

  • 未ログイン時に回答情報を参照しない挙動や、返却結果の内容を検証するテストを追加しました。

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: ASSERTIVE

Plan: Pro

Run ID: 6f0a4302-78a4-422d-8295-715df389d5b2

📥 Commits

Reviewing files that changed from the base of the PR and between e482684 and 10e8a04.

📒 Files selected for processing (1)

• src/lib/types/task.ts

---

📝 Walkthrough

Walkthrough

TaskResult.user_id の型を string | undefined に変更し、サービス層の複数の公開 API（getTaskResults ほか）で userId 引数を拡張。匿名時は DB アクセスをスキップして空 Map で結果生成。対応テストも追加。

Changes

匿名ユーザー対応：タスク結果サービス

Layer / File(s)	Summary
TaskResult 型定義変更 src/lib/types/task.ts	TaskResult.user_id を `string
サービス API と匿名分岐実装 src/lib/services/task_results.ts	getTaskResults、getTaskResultsOnlyResultExists、getTasksWithTagIds、createDefaultTaskResult、mergeTaskAndAnswer の userId を string | undefined に拡張。userId が undefined の場合に getAnswers DB アクセスをスキップして空 Map を使用する分岐を実装。
匿名ケーステスト src/test/lib/services/task_results.test.ts	getTaskResults・getTaskResultsOnlyResultExists に対して userId = undefined 時に getAnswers が呼ばれない、全タスクがデフォルト返却・空配列返却されることを検証するテストを追加。

Sequence Diagram

sequenceDiagram
  participant Client
  participant getTaskResults
  participant createTaskResults
  participant answer_crud
  participant mergeTaskAndAnswer

  Client->>getTaskResults: getTaskResults(undefined)
  getTaskResults->>createTaskResults: userId = undefined
  alt userId === undefined
    createTaskResults->>createTaskResults: 空Mapを作成
  else userId存在
    createTaskResults->>answer_crud: getAnswers(userId)
    answer_crud-->>createTaskResults: 回答Map返却
  end
  createTaskResults->>mergeTaskAndAnswer: 結果とMapをマージ
  mergeTaskAndAnswer-->>getTaskResults: TaskResult[]
  getTaskResults-->>Client: 返却

Loading

🎯 2 (Simple) | ⏱️ ~10 分

Possibly related issues

• #3676: このPRで実装した変更（userId を string | undefined に変更し、getAnswers 呼び出しを匿名時スキップ）は issue #3676 が要求する内容と完全に一致。

Poem

🔓 ログインなくても旅はできる、
undefined を抱えて進む勇気、
getAnswers は呼ばれず静かに空へ、
匿名の足跡、デフォルトで刻む、
型の海に | undefined が咲いた 🌸

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	タイトルは、匿名ユーザーに対する getAnswers のフルスキャン回避という PR の主要な目的を正確に反映しており、変更内容の核となるパフォーマンス改善が明確に示されている。
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/skip-getanswers-for-anonymous

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[KATO-Hiro]

@coderabbitai review

[coderabbitai]

✅ Action performed

Review finished.

Note: CodeRabbit is an incremental review system and does not re-review already reviewed commits. This command is applicable only when automatic reviews are paused.

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@src/lib/types/task.ts`:
- Around line 64-67: The TaskResult interface is missing TSDoc documentation,
which makes the public contract unclear to consumers, especially regarding the
user_id field that can be undefined for anonymous (logged-out) results. Add a
comprehensive TSDoc block to the TaskResult interface that documents what the
type represents and explicitly clarifies that user_id is optional and undefined
for anonymous results. Follow the src/**/*types/** coding guideline that
requires TSDoc on all exported types.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: ASSERTIVE

Plan: Pro

Run ID: 1c42bbdd-38bb-495a-9140-6f34ba91ec29

📥 Commits

Reviewing files that changed from the base of the PR and between 86ef295 and e482684.

📒 Files selected for processing (3)

• src/lib/services/task_results.ts
• src/lib/types/task.ts
• src/test/lib/services/task_results.test.ts

[KATO-Hiro]

LGTM