[Feature Request] Better integration with forms

[Rick-Phoenix]

Feature description:

When trying to validate a value, validation should not fail if the value is not yet a message, but instead create the message and then validate it.

Problem it solves or use case:

Some libraries such as Tanstack Form (and hopefully, superform too) offer native support for Standard Schema validation, but this does not integrate well with the current logic of protovalidate-es because validation first requires creating a message with create().

Proposed implementation or solution:

In the call to validateUnsafe, do not reject validation outright if the value is not yet a message, but rather, if it isn't one, create a new message with the given descriptor

function validateUnsafe(registry, celMan, planner, schema, message, failFast) {
    const messageTypeName = message.$typeName;

    // Replace this part here...
    if (!isMessage(message, schema)) {
        throw new RuntimeError(`Cannot validate message ${messageTypeName} with schema ${schema.typeName}`);
    }

Contribution:

I am willing to implement it myself, if there are no reasons for which it cannot be implemented. I am ok with others implementing it too.

Examples or references:

Here is a stackblitz repo with the example I was working on.

As you can see, the validators such as onSubmit, onChange and so on must be a pure implementation of the Standard Schema, so if you swap completeValidator with greetValidator it won't work. Whereas if you include the message creation logic in the validator as I did for completeValidator, you can just seamlessly use that validator to validate form data on the client side, which is a major benefit of using this library.

The simple wrapper solution I implemented is also an alternative, but unless there are reasons to not do so, I think it would be a good idea to include that logic in the validator itself so that it can be used easily with form libraries.