Localize update confirmation and first-run notifications

The update prompt speaks Chinese and points What's new at the
OmarchyCN releases page; the Wi-Fi, update, keybindings, dictation,
and default-agent first-run notices follow.

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

install/user/first-run/setup-agent.hook

@@ -5,7 +5,7 @@ set -e
 # Omarchy ships no default agent, so invite once rather than picking one. An
 # agent already chosen means the invitation has nothing to offer.
 if [[ -z $(omarchy-default-agent) ]] && omarchy-done ensure agent-setup-invitation; then
-  omarchy-notification-send -u critical -g 󰚩 "Set your default agent" \
-    "Let your favorite agent help with Omarchy." \
+  omarchy-notification-send -u critical -g 󰚩 "设置默认 Agent" \
+    "让你常用的 Agent 帮你使用 Omarchy。" \
     --exec omarchy menu summon setup.default.agent
 fi