Notify about illegal chars in title, and list them

Is your feature request related to a problem? Please describe.
I'm always frustrated when I try to add some characters in a Note's title, and that character silently disappear. E.g. I tried to add "R:" at the start of a note, and the colon disappeared silently. I needed to click rename once again, trying another character,and validate to check if it's allowed or not.

Describe the solution you'd like

1. Add the list of illegal characters in the Note Settings, so one could browse them before trying funny things
2. a. We should at least have a toaster saying a char has been removed for file compatibility reasons
3. b. A better user experience would be blocking the validation, with an inline message below the text input saying ":" is not allowed here

Start by tracing the Note title rename and validation flow, then inspect the Note Settings UI mentioned in the issue. Decide how the existing behavior handles illegal characters before choosing between a toaster and inline validation. Done means users can see the illegal-character list and receive clear feedback instead of silent removal.