Snapshot friend_back worktree for local merge

Source HEAD: 9d7e220f14
Includes uncommitted project changes and new project files.
Align shared text line endings and executable flags with Friendship-and-chat-api.
Normalize new text to LF; exclude .workbuddy local assistant memory.
Original friend_back checkout is unchanged.

sql/mysql/system/system_menu_subaccount_gender.sql

@@ -0,0 +1,17 @@
+-- 后台菜单与授权：子账号管理 + 会员管理拆分（男号/女号）
+-- 执行库：chat_v1
+-- 1) 新增菜单（幂等：先删后插）
+DELETE FROM system_menu WHERE id IN (5810, 5820, 5821);
+INSERT INTO system_menu (id, name, permission, type, sort, parent_id, path, icon, component, component_name, status, visible, keep_alive, always_show, creator, updater, deleted)
+VALUES
+(5810, '子账号管理', 'system:sub-account:manage', 2, 20, 0, '/sub-account', 'ep:user', 'system/subaccount/index', 'SystemSubAccount', 0, b'1', b'1', b'1', '1', '1', b'0'),
+(5820, '男号管理', 'member:user:query', 2, 1, 2262, 'male-user', 'ep:male', 'member/user/male', 'MemberUserMale', 0, b'1', b'1', b'1', '1', '1', b'0'),
+(5821, '女号管理', 'member:user:query', 2, 2, 2262, 'female-user', 'ep:female', 'member/user/female', 'MemberUserFemale', 0, b'1', b'1', b'1', '1', '1', b'0');
+
+-- 2) 授权给「APP管理员」角色（AppHolder 当前使用的角色）
+DELETE FROM system_role_menu WHERE role_id = 158 AND menu_id IN (5810, 5820, 5821);
+INSERT INTO system_role_menu (role_id, menu_id, creator, updater, deleted, tenant_id)
+VALUES
+(158, 5810, '1', '1', b'0', 1),
+(158, 5820, '1', '1', b'0', 1),
+(158, 5821, '1', '1', b'0', 1);

sql/mysql/system/system_sub_account.sql

@@ -0,0 +1,17 @@
+-- 子账号管理：holder 与 子账号/专属角色 的绑定关系
+-- 执行位置：chat_v1 库
+CREATE TABLE IF NOT EXISTS `system_sub_account` (
+    `id`             bigint       NOT NULL AUTO_INCREMENT COMMENT '主键',
+    `holder_user_id` bigint       NOT NULL COMMENT '管理者用户编号（system_users.id）',
+    `sub_user_id`    bigint       NOT NULL COMMENT '子账号用户编号（system_users.id）',
+    `role_id`        bigint       NOT NULL COMMENT '子账号专属角色编号（system_role.id）',
+    `creator`        varchar(64)  NULL DEFAULT '' COMMENT '创建者',
+    `create_time`    datetime     NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',
+    `updater`        varchar(64)  NULL DEFAULT '' COMMENT '更新者',
+    `update_time`    datetime     NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '更新时间',
+    `deleted`        bit(1)       NOT NULL DEFAULT b'0' COMMENT '是否删除',
+    `tenant_id`      bigint       NOT NULL DEFAULT 0 COMMENT '租户编号',
+    PRIMARY KEY (`id`),
+    KEY `idx_holder_user_id` (`holder_user_id`),
+    KEY `idx_sub_user_id` (`sub_user_id`)
+) ENGINE = InnoDB COMMENT '后台子账号表';