message: add field methods docs
diff: VeeValidate maps HTML elements and Vue components that are under validation to instances of `fields`, while this class not exposed to be used publicly you can find Its API very useful if you are planning to do some lower-level actions.
  +::: warning
  + Any undocumented properties/methods are not intended for public use.
  +:::
  +
  ## Getting the field instance
  Getting a field instance is straightforward, you can use the `Validator.fields.find` method to get the field instance.
  @@ -19,6 +23,12 @@ const field = this.$validator.fields.find({ id: 'fieldId' });
  ## API
  +::: danger
  + Careful when using the field API, as it may disrupt the validator operations and may produce unintended results.
  +:::
  +
  +### Constructor
  +
  ### Properties
  |Name |Type |Default |Description |
  @@ -54,3 +64,14 @@ const field = this.$validator.fields.find({ id: 'fieldId' });
  ### Methods
  +|Signature |Return Type | Description |
  +|---------|---------|---------|
  +|matches(options: FieldMatchOptions) | `boolean` | Checks if the field matches the specified matching object criteria. |
  +|update(options: FieldOptions) | `void` | Updates the field properties and re-adds the listeners and syncs the classes applied. |
  +|reset() | `void` | Resets the field flags to their initial state. |
  +|setFlags(flags: { [string]: boolean }) | `void` | Updates the field flags and also updates the specified field counterparts eg. valid/invalid. |
  +|unwatch(tag?: RegExp) | `void` | Removes the listeners that has a matching tag or removes all if none is provided. |
  +| updateClasses() | `void` | Syncs the classes being applied on the element with the flags if enabled.|
  +| updateAriaAttrs() | `void` | Syncs the aria attributes applied on the element with the flags if enabled. |
  +| updateCustomValidity() | `void` | Syncs the constrained API validation message with the first error message for this field. |
  +| destroy() | `void` | Removes all listeners and dependencies of the field. |
  