Change completion start to 2 for nvim

[tetigi]

The current complete_length of 0 is overwhelming and constantly bombarding the autocomplete with every possible suggestion in the namespace, even when your cursor is just chilling out as you think about what to write next. Setting it to 2 makes a bit more sense as a default option.

[SevereOverfl0w]

Is there a user configuration place for this? 0 is technically what we are capable of, unless ncm2 provides specific guidance on this?

[tetigi]

I had a short dig, but couldn't immediately surface an obvious way to change it (although I did not look particularly hard and I'm definitely not a ncm expert). I suppose it is a matter of opinion, but when the suggestion was popping up when I hadn't written anything, it would suggest every possibility, which isn't particularly helpful.

[tetigi]

You're right that it can be set in user settings, but I still think 2 or 3 is worth considering as a sensible default, as this is what ncm is by default for high priority completers. (see https://github.com/ncm2/ncm2/blob/160e2e33d515f67154840844d8304722b679df90/doc/ncm2.txt#L221)