coding standards for bigger projects
In my experience (15 years in industry, 30 total), this does not matter. What matters is having good developers who understand code written in ANY valid style. I currently work at a large bank, and there's 2 different bracket styles being used in our code, and nobody cares. Good developers don't care about this. We care a lot more about the code being valid, error-free, and efficient. If you do that, I don't care where your brackets are.

Yes, there are style guides for C++ but you don't need to use them. This is a good one though...

http://google-styleguide.googlecode.com/svn/trunk/cppguide.html

I am not aware of any style tools that integrate into Arduino IDE. There are some style tools that integrate into Eclipse though - and if this is important to you and your team, I strongly suggest using Eclipse for development. The Arduino IDE isn't really for large projects.

http://astyleclipse.sourceforge.net/ - but Eclipse doesn't really need this, it has a pretty good built-in formatter.