"suggests how to amend claims for allowance"
If examiner suggested any specific amendment(s) to your claim(s) to put your claims in condition of allowance and has asked you to send response to final rejection then you should be a relieved man, you are almost through. If that "how to" was just academic, then all the niceties were of 'Null' utility to you.
1. How to file after final response and in what format?
Format and method for filing response to final office action from USPTO is same as the format for response and method for filing response followed by you for filing response to non-final office action.
Only this time you ought to mention (i) it is a response to final office action, (ii) provide summary of interview with examiner, (iii) mention if you are following examiner's suggestions for claim amendment to put claims in condition of allowance and (iv) restrict your amendments to examiner's suggestion and/or limitations laid down by 37 CFR 1.116(b) Ref-1.
In the absence of specific suggestion for amendment to claims to put them in condition of allowance and amendments not conforming to limits of 37 CFR 1.116(b) mentioned above, I think, RCE is the option to go for with your amendments.
2. What can be included in after final?
Excerpt from MPEP 714.13 : Ref-2
Except where an amendment merely cancels claims, adopts examiner
suggestions, removes issues for appeal, or in some other way requires
only a cursory review by the examiner, compliance with the requirement
of a showing under 37 CFR 1.116(b)(3) is expected in all amendments
after final rejection.
3. Do you know any examples (patent numbers) of patents with after final prosecution?
I would rather suggest a method. Go to PublicPair Ref-3. Enter any application number pre or post to your application number. Look at 'Image file wrapper'. Most likely you will hit desired result.
4. Are there any special pitfalls of after final prosecution(except those that already apply to normal patent prosecution)?
See answer to 2 above. Bonus expected is 'examiner deciding to enter your amendment of claims for catering to appeal issues without allowing your claims' which may introduce new matter for new search and new objections during RCE or such future prosecution actions.
Kindly take note : Please don't consider it as legal advice. If your purse permits, it is always advisable to take legal advice from qualified professional.