…lt` annotation in schemas

Only constant values can be passed to attributes, but an attribute's constructor can convert a parameter to the desired Type.

…o 'JsonPropertyDefault'

…n from `pattern`

They are not mutually-inclusive. They have different purposes and can be used without the other.

also, update property descriptions and add comments

…ibutes

…for CommitDateFormat

…nConstants

…operty attributes

…faultLabelNumberPattern

And fix pattern inconsistency. It was failing tests.

…ir properties

…, GitHubFlow

Switches should not have values and some keys' values should not be enclosed with double-quotes. Both were leading to fatal errors.

…nd recommend running build.ps1 with "build,BuildPrepare"

…zing Nullable<DateTimeOffset>

Nullable types seem to ignore the types' built-in JSON converters
i.e. DateTimeOffset <=> string, but DateTimeOffset? <=> object or null