feat: add notify command, modify sidekick with tmux

fish/functions/notify-done.fish

@@ -0,0 +1,24 @@
+function notify-done --description '前置包装：运行命令并在完成时发送 OSC 777 通知'
+    if test (count $argv) -eq 0
+        echo "Usage: notify-done <command> [args...]" >&2
+        return 2
+    end
+
+    set -l start (date +%s)
+    $argv
+    set -l rc $status
+    set -l elapsed (math (date +%s) - $start)
+    set -l human (_notify_human_duration (math $elapsed \* 1000))
+
+    set -l label
+    if test $rc -eq 0
+        set label "完成: $argv[1]"
+    else
+        set label "失败 exit=$rc: $argv[1]"
+    end
+
+    set -l body "$human · "(hostname -s)" · "(string join ' ' $argv)
+
+    _notify_emit "$label" "$body"
+    return $rc
+end