Remove extraneous references to value in error messages

[bufdev]

Whenever you get a validation error, it reads like this:

validation errors:
 - foo: value must be greater than 0
 - bar: value must not contain "baz"

The "value" messaging is weird to me. It feels much more natural to have:

validation errors:
 - foo: must be greater than 0
 - bar: must not contain "baz"

I would even argue for:

validation errors:
 - "foo" must be greater than 0
 - "bar" must not contain "baz"

But that's a step too far for this simple PR.

[github-actions]

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Build	Format	Lint	Breaking	Updated (UTC)
✅ passed	✅ passed	✅ passed	✅ passed	Nov 25, 2025, 7:20 PM

[timostamm]

I agree that this results in a more natural error message.

However, that won't be the case when the message is shown next to an input field in a form. You wouldn't include the field path in the error message, and the error message needs to stand on it's own. This works for value must not contain "baz", but much less so for must not contain "baz" - it's not a full sentence.

[bufdev]

when the message is shown next to an input field in a form.

I do not think there is a single instance of this in actual protovalidate usage. When this happens, we can adjust the error message accordingly. Otherwise, this is a QOL improvement for every other protovalidate user - can you get this merged?