issue #2243 -- prefer f-strings over %-interpolation

edited docs to prefer f-strings, then str.format(), and remove %-interpolation

additional ad-hoc documentation fixes, as opportunities seen:
- replace Built-In Function (BIF) "min" variable with "mins"
- prefer BIF str(var) over "%s" % var
- reformat some code examples to clarify multiple args passed to functions
- change some single-quote strings to double-quotes for consistency
- fix mismatched parens

misc edits:
- add .vscode/ to gitignore

docs/source/Howto/Web-Character-Generation.md

@@ -246,8 +246,12 @@ def creating(request):
                 user.db._playable_characters.append(char)
                 # add the right locks for the character so the account can
                 #  puppet it
-                char.locks.add("puppet:id(%i) or pid(%i) or perm(Developers) "
-                    "or pperm(Developers)" % (char.id, user.id))
+                char.locks.add(" or ".join([
+                    f"puppet:id({char.id})",
+                    f"pid({user.id})",
+                    "perm(Developers)",
+                    "pperm(Developers)",
+                ]))
                 char.db.background = background # set the character background
             return HttpResponseRedirect('/chargen')
     else:
@@ -332,8 +336,12 @@ def creating(request):
                 user.db._playable_characters.append(char)
                 # add the right locks for the character so the account can
                 #  puppet it
-                char.locks.add("puppet:id(%i) or pid(%i) or perm(Developers) "
-                    "or pperm(Developers)" % (char.id, user.id))
+                char.locks.add(" or ".join([
+                    f"puppet:id({char.id})",
+                    f"pid({user.id})",
+                    "perm(Developers)",
+                    "pperm(Developers)",
+                ]))
                 char.db.background = background # set the character background
             return HttpResponseRedirect('/chargen')
     else: