No longer need to-string when using concat. However, it is still needed if the token string consists of a single token.

This avoids a troublesome circular import.

…tion time.

 - Add coercion after call to 'getValueAndResolveTokens`, since the non-expression pathway here skips the coercion logic in parsing_context
 - Remove 'string | Formatted' typing and 'text instanceof Formatted' checks
 - Add Coercion support for 'Formatted', along with dedicated serialization
 - Use Coercion when parsing expected.kind === 'formatted' instead of directly creating a FormatExpression. This is necessary to accommodate expressions such as 'coalesce' that introduce a typeAnnotation.