feat(board-generator): add board code generator and sample CRUD artifacts

Add Node.js CLI tool with Handlebars templates for generating standard CRUD artifacts: Java entity, service, DAO, controller, MyBatis mapper XML, and Vue frontend pages.
Also generate the full SampleTableBoard CRUD reference implementation, update README with backend execution instructions, and add project plan documentation.

tools/board-generator/templates/dao.hbs

@@ -0,0 +1,46 @@
+package {{daoPackage}};
+
+import java.util.List;
+
+import org.apache.ibatis.session.SqlSession;
+import org.springframework.stereotype.Repository;
+
+import {{entityFqcn}};
+
+@Repository
+public class {{daoName}} {
+
+	private static final String MAPPER = "{{mapperNamespace}}.";
+
+	private final SqlSession sqlSession;
+
+	public {{daoName}}(SqlSession sqlSession) {
+
+		this.sqlSession = sqlSession;
+	}
+
+	public List<{{entityName}}> select{{entityName}}List() {
+
+		return sqlSession.selectList(MAPPER + "select{{entityName}}List");
+	}
+
+	public {{entityName}} select{{entityName}}({{primaryKeyJavaType}} {{primaryKeyProperty}}) {
+
+		return sqlSession.selectOne(MAPPER + "select{{entityName}}", {{primaryKeyProperty}});
+	}
+
+	public void insert{{entityName}}({{entityName}} {{entityVarName}}) {
+
+		sqlSession.insert(MAPPER + "insert{{entityName}}", {{entityVarName}});
+	}
+
+	public void update{{entityName}}({{entityName}} {{entityVarName}}) {
+
+		sqlSession.update(MAPPER + "update{{entityName}}", {{entityVarName}});
+	}
+
+	public void delete{{entityName}}({{primaryKeyJavaType}} {{primaryKeyProperty}}) {
+
+		sqlSession.delete(MAPPER + "delete{{entityName}}", {{primaryKeyProperty}});
+	}
+}