docs: standardize English terminology in with-react-query documentation

[Gaic4o]

Background

• Translate React Query related terms (query, mutation, etc.) to English
• Unify Feature-Sliced Design architecture terminology in English

Reverted React Query terminology from Korean to original English to prevent meaning distortion and maintain technical accuracy. English terms provide better clarity and consistency with official documentation.

[Copilot]

Pull Request Overview

This PR standardizes English terminology in the Korean localization of the with-react-query guide by reverting translated React Query and FSD terms back to their original English for clarity and consistency.

• Reverted Korean translations of React Query concepts (query, mutation, pagination, etc.) to English.
• Unified Feature-Sliced Design folder and API naming in English.
• Updated headings, comments, and link texts to use consistent English terms.

Comments suppressed due to low confidence (4)

i18n/kr/docusaurus-plugin-content-docs/current/guides/tech/with-react-query.mdx:8

• [nitpick] Consider wrapping directory names like entities in backticks (e.g., entities별로) to clearly distinguish code/folder names from regular text.

### 해결책 — entities별로 분리하기

i18n/kr/docusaurus-plugin-content-docs/current/guides/tech/with-react-query.mdx:10

• [nitpick] For consistency, wrap both entities and entity in backticks to indicate code/folder names, and ensure singular/plural usage matches the actual directory structure.

프로젝트가 이미 entities 단위로 구성되어 있으며, 각 요청이 단일 entity에 해당한다면, entities별로 코드를 분리하는 것이 좋습니다. 예를 들어, 다음과 같은 디렉토리 구조를 사용할 수 있습니다:

i18n/kr/docusaurus-plugin-content-docs/current/guides/tech/with-react-query.mdx:118

• [nitpick] To maintain style consistency, consider formatting Request as code (Request 조직화) or translating to Korean (요청 조직화) to avoid mixing languages in headings.

## Request 조직화

i18n/kr/docusaurus-plugin-content-docs/current/guides/tech/with-react-query.mdx:229

• [nitpick] Consider wrapping segments in backticks or capitalizing it consistently (e.g., api segments or API Segments) to match code formatting elsewhere.

getPosts 함수는 `api` segments의 `get-posts.ts` 파일에서 정의됩니다.