chore: refactoring backend

[Myxogastria0808]

No description provided.

[Copilot]

Pull request overview

This PR refactors backend route handlers to move business logic into a dedicated application layer (use cases + shared helpers), while updating validator exports for the /api/info/* responses and adding 404 to the shared OpenAPI error schema.

Changes:

• Migrate DB/query logic out of presentation routes into products/backend/src/application/* use cases and shared utilities.
• Add a new protected session route module and replace the old check route wiring.
• Rename info response schemas/types in the validator package (and adjust an amount constraint).

Reviewed changes

Copilot reviewed 18 out of 18 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
products/validator/src/response/info.ts	Renames info response schemas/types and loosens amount validation.
products/validator/src/index.ts	Re-exports renamed info response schemas/types.
products/backend/src/presentation/utils/types.ts	Removes presentation-layer TransactionType (moved to application layer).
products/backend/src/presentation/share/error.ts	Adds 404 to shared OpenAPI error responses.
products/backend/src/presentation/routes/userProfile.ts	Delegates profile read/update to application use cases; adds 404 to schema for GET.
products/backend/src/presentation/routes/session.ts	New session-check route delegating to application use case.
products/backend/src/presentation/routes/info.ts	Delegates info endpoints to application use cases.
products/backend/src/presentation/routes/group.ts	Delegates group endpoints to application use cases.
products/backend/src/presentation/routes/check.ts	Removes old session-check route implementation.
products/backend/src/presentation/api.protected.ts	Switches routing from check to new session route module.
products/backend/src/application/utils/user.ts	Adds shared user name formatting + user lookup helpers.
products/backend/src/application/utils/types.ts	Adds shared application-layer types (DB, transaction aggregation, user info).
products/backend/src/application/utils/group.ts	Adds group membership validation + group member fetch helper.
products/backend/src/application/utils/db.ts	Centralizes Drizzle DB connection creation.
products/backend/src/application/userProfile.ts	Adds profile use cases for get/update.
products/backend/src/application/session.ts	Adds session-check use case.
products/backend/src/application/info.ts	Adds info endpoints’ use cases (groups list, transactions aggregation, repayment delete).
products/backend/src/application/group.ts	Adds group endpoints’ use cases (create/join/info/debt history/register/delete/cancel).

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[Copilot]

getUserInfo throws an HTTP 500 when the user row is missing. This same refactor introduces a 404 path for missing users in getUserProfileUseCase, so this behavior is inconsistent and can surface as an unexpected 500 (e.g., if the session references a deleted user). Consider returning a 404 (or 401) here and updating any route schemas that rely on this helper accordingly.

Suggested change

	// ユーザが存在しない場合はエラー
	if (userNameInfo.length === 0) {
	throw new HTTPException(500, { message: 'Internal Server Error' });
	// ユーザが存在しない場合は 404 を返す
	if (userNameInfo.length === 0) {
	throw new HTTPException(404, { message: 'User not found' });

[Copilot]

getInfoAboutGroupsTheUserBelongsToUseCase calls getGroupMembers once per group ID. Since getGroupMembers performs multiple DB queries, total round-trips scale with the number of groups (N+1 style at the group level). Consider batching memberships for all groups in one query and resolving user names in one getUserNameMap call to keep query count bounded.

Suggested change

	// createdByのユーザ名の取得
	const uniqueCreatedByIds = Array.from(new Set(groupData.map((group) => group.createdBy)));
	const createdByNameMap = await getUserNameMap(db, uniqueCreatedByIds);
	// グループメンバーのユーザ名の取得
	const uniqueGroupIds = Array.from(new Set(groupData.map((group) => group.id)));
	const groupMembersEntries = await Promise.all(
	uniqueGroupIds.map(async (groupId) => {
	const members = await getGroupMembers(db, groupId);
	const formattedMembers = members.map((member) => {
	return {
	user_id: member.id,
	user_name: member.name,
	} as GetInfoAboutGroupsTheUserBelongsToResponseMemberElementSchemaType;
	});
	return [groupId, formattedMembers] as const;
	})
	);
	const groupMembersMap: Map<string, GetInfoAboutGroupsTheUserBelongsToResponseMemberElementSchemaType[]> = new Map(
	groupMembersEntries
	);
	// グループ情報の整形
	const groupInfo: GetInfoAboutGroupsTheUserBelongsToResponseGroupElementSchemaType[] = await Promise.all(
	groupData.map(async (groupData) => {
	// createdByのユーザ名取得
	const createdByName = createdByNameMap.get(groupData.createdBy);
	// グループメンバー情報の取得（N+1 クエリを避けるため一括で取得）
	const uniqueGroupIds = Array.from(new Set(groupData.map((group) => group.id)));
	const groupMemberships = await db
	.select({
	groupId: groupMembership.groupId,
	userId: groupMembership.userId,
	})
	.from(groupMembership)
	.where(inArray(groupMembership.groupId, uniqueGroupIds));
	// createdBy と メンバー両方のユーザ名を一括で取得
	const uniqueCreatedByIds = Array.from(new Set(groupData.map((group) => group.createdBy)));
	const memberUserIds = Array.from(new Set(groupMemberships.map((membership) => membership.userId)));
	const allUserIds = Array.from(new Set([...uniqueCreatedByIds, ...memberUserIds]));
	const userNameMap = await getUserNameMap(db, allUserIds);
	// グループごとのメンバー一覧を構築
	const groupMembersMap: Map<
	string,
	GetInfoAboutGroupsTheUserBelongsToResponseMemberElementSchemaType[]
	> = new Map();
	for (const membership of groupMemberships) {
	const userName = userNameMap.get(membership.userId);
	if (userName === undefined) {
	throw new HTTPException(500, { message: 'Internal Server Error' });
	}
	const memberList =
	groupMembersMap.get(membership.groupId) ?? [];
	const member: GetInfoAboutGroupsTheUserBelongsToResponseMemberElementSchemaType = {
	user_id: membership.userId,
	user_name: userName,
	};
	groupMembersMap.set(membership.groupId, [...memberList, member]);
	}
	// グループ情報の整形
	const groupInfo: GetInfoAboutGroupsTheUserBelongsToResponseGroupElementSchemaType[] = await Promise.all(
	groupData.map(async (groupData) => {
	// createdByのユーザ名取得
	const createdByName = userNameMap.get(groupData.createdBy);

[Copilot]

The response sets group_name to the group's display name (groupData[0].name). In the validator package, getGroupInfoResponseSchema currently defines group_name as a UUID, so the emitted OpenAPI/types will not match the actual runtime response. Align the validator schema (or the response field) so group_name is validated/typed as a non-empty string.