Set default extra-args to skip update checking and release notes

[blahgeek]

this one is a little bit opinionated.. personally I think it makes sense to skip these possible interruption during startup, to prevent aidermacs failing to send commands to the backend

[MatthewZMD]

Since Aider's LLM model capabilities is hard depended on aider's version, I think it's reasonable to remind user to update as much as possible. If we really want this feature, we can turn them into defcustoms. What do you think?

[blahgeek]

I guess you have a point. If the user solely use aider in aidermacs, then it seems to be a bad idea to completely skip upgrade checking which would means that the user would never get upgrades.

My initial goal is to prevent the interruption of the startup, so that if the user implicitly start the backend by running some commands (e.g. "code change"), the backend would always be ready to accept the command, instead of losing the command input due to interruption. But now that I think about it, maybe it's not a good tradeoff given the low frequency of updates.

I think I would close this PR then. Thanks.

[MatthewZMD]

Thank you for all the contributions!