docs(tailscale): 更新数据目录路径和说明

将数据目录从 `./data/var/lib` 改为 `./data/state` 并更新挂载路径至 `/var/lib/tailscale`
添加关于目录权限的重要提示说明

apps/tailscale/latest/docker-compose.yml

@@ -5,7 +5,7 @@ services:
     hostname: ${HOSTNAME:-tailscale}
     restart: always
     volumes:
-      - ./data/var/lib:/var/lib
+      - ./data/state:/var/lib/tailscale
       - /dev/net/tun:/dev/net/tun
     cap_add:
       - NET_ADMIN
@@ -15,7 +15,7 @@ services:
     environment:
       - TS_AUTHKEY=${TS_AUTHKEY}
       - TS_USERSPACE=${TS_USERSPACE:-false}
-      - TS_STATE_DIR=/var/lib
+      - TS_STATE_DIR=/var/lib/tailscale
       - TS_ROUTES=${TS_ROUTES:-}
       - TS_ACCEPT_DNS=${TS_ACCEPT_DNS:-true}
       - TS_EXTRA_ARGS=${TS_EXTRA_ARGS:-}