[feature/backend] implement /users handler + switch to username + add display name + user management cli

backend/config/config.yaml.example

@@ -0,0 +1,36 @@
+database:
+  driver: sqlite3
+  # SQLite DSN 说明：
+  # - file:tss.db => 相对路径，在当前目录创建 tss.db
+  # - cache=shared => 启用共享缓存，提高性能
+  # - _fk=1 => 启用外键约束
+  # - mode=rwc => 如果数据库不存在则创建（read-write-create）
+  dsn: "file:tss.db?cache=shared&_fk=1&mode=rwc"
+
+server:
+  port: 8080
+  host: localhost
+
+jwt:
+  secret: your-jwt-secret-here  # 在生产环境中应该使用环境变量
+  expiration: 24h
+
+storage:
+  driver: local
+  local:
+    root: storage
+    base_url: http://localhost:8080/storage
+
+logging:
+  level: debug
+  format: console
+
+rate_limit:
+  enabled: true
+  requests: 100
+  duration: 1m
+
+access_log:
+  enabled: true
+  format: combined
+  output: stdout