[Feature]: Support notification sound

[tobeycodes]

What would you like to be added?

The notification systems for other agents allows me to really customize how notifications work. E.g. change the message and/or use a sound. It would be nice if we can do something similar in auggie. I'm not always looking at my screen so it would be useful to customize this so I can send notifications in different ways.

export const NotificationPlugin = async ({
  project: _project,
  client: _client,
  $,
  directory: _directory,
  worktree: _worktree,
}) => {
  return {
    event: async ({ event }) => {
      if (event.type === "session.idle") {
        await $`osascript -e 'display notification "OpenCode Code needs your attention" with title "OpenCode" sound name "Glass"'`;
      }
    },
  };
};

Why is this needed?

Makes running multiple auggie clients in parallel easier or being notified in different ways when action is required

Possible solution or alternatives

No response

Additional context

No response