Meanwhile, I found the source of the problem. This morning, after I didn’t find anything suspicious in the debug log, I came up with the idea to change the domain used to .org (I made the appropriate changes to the configuration of the local DNS server and Caddyfile) - and everything was OK. A quick internet search brought me here: proxy - iOS Safari development ".local" domain issue - Stack Overflow
Bottom line: Apple seems to be following RFC 6762, which reserves the .local domain for multicast DNS, and Safari does not recognize addresses in this domain as valid addresses.
Domain .lan looks like a good alternative but doesn’t work well in Safari either…
Thank you, @francislavoie , for your attention.
These are not optional if you have any certificates
Yes, I know this, this is my starting configuration, and there is a lot of copy-paste “garbage” from the tutorials I read 
P.S. I mark this post as a solution, although I have not found a good solution yet …