docs(README): bump Git prerequisite to >= 2.41 and sync localized READMEs

Bump the Git prerequisite version hint from >= 2.38 to >= 2.41, and add
the Prerequisites section to the ja/ko/ru localized READMEs which were
missing it.

README.ja-JP.md

@@ -92,6 +92,10 @@ Open Code Reviewのコア哲学は、決定論的エンジニアリングとエ
 
 ## 使い方
 
+### 前提条件
+
+- **Git >= 2.41** — Open Code Review は diff 生成、コード検索、リポジトリ操作に Git を利用します。
+
 ### CLI
 
 #### インストール

README.ko-KR.md

@@ -92,6 +92,10 @@ agent의 강점은 동적 판단과 동적 context 검색이 중요한 지점에
 
 ## 사용 방법
 
+### 사전 요구 사항
+
+- **Git >= 2.41** — Open Code Review는 diff 생성, 코드 검색, 저장소 작업에 Git을 사용합니다.
+
 ### CLI
 
 #### 설치

README.md

@@ -94,7 +94,7 @@ The agent's strengths are concentrated where they matter most — dynamic decisi
 
 ### Prerequisites
 
-- **Git >= 2.38** — Open Code Review relies on Git for diff generation, code search, and repository operations.
+- **Git >= 2.41** — Open Code Review relies on Git for diff generation, code search, and repository operations.
 
 ### CLI
 

README.ru-RU.md

@@ -92,6 +92,10 @@ Open Code Review — это CLI-инструмент для код-ревью н
 
 ## Как использовать
 
+### Предварительные требования
+
+- **Git >= 2.41** — Open Code Review использует Git для генерации diff, поиска по коду и операций с репозиторием.
+
 ### CLI
 
 #### Установка

README.zh-CN.md

@@ -94,7 +94,7 @@ Open Code Review 的核心设计理念是将确定性工程与 Agent 结合，
 
 ### 前置条件
 
-- **Git >= 2.38** — Open Code Review 依赖 Git 进行 diff 生成、代码搜索和仓库操作。
+- **Git >= 2.41** — Open Code Review 依赖 Git 进行 diff 生成、代码搜索和仓库操作。
 
 ### CLI