Use full -Syu transactions, no partial upgrades

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QKxGW1raAWaqeU8WdHsMsp

docs/pacman-repo.md

@@ -19,7 +19,7 @@ Server = https://git.zacharyzhang.com/api/packages/ZacharyZhang-NY/arch/omarchyc
 EOF
 
 # 3. 安装 keyring（含 registry 与 release 两把公钥及信任配置）
-sudo pacman -Sy omarchycn-keyring
+sudo pacman -Syu omarchycn-keyring
 ```
 
 ## 密钥

packages/build-keyring.sh

@@ -7,7 +7,7 @@ ROOT=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")/.." && pwd)
 
 docker run --rm -v "$ROOT:/src:ro" -v "$ROOT/packages/out:/out" archlinux/archlinux:latest bash -c '
 set -euo pipefail
-pacman -Sy --noconfirm --quiet base-devel > /dev/null
+pacman -Syu --noconfirm --quiet base-devel > /dev/null
 useradd -m builder
 cp -r /src/packages/omarchycn-keyring /home/builder/pkg
 cp /src/cn/keys/omarchycn-registry.asc /home/builder/pkg/omarchycn-registry.key