Recognise local references in dynamic blocks

[radeksimko]

Currently we do not recognise "local" references within the dynamic block, such as setting.* in this example:

resource "aws_elastic_beanstalk_environment" "tfenvtest" {
  # ...
  dynamic "setting" {
    for_each = var.settings
    content {
      namespace = setting.value["namespace"] # HERE
      name      = setting.value["name"] # HERE
      value     = setting.value["value"] # HERE
    }
  }
}

This affects completion, hover, go-to-*, and semantic token highlighting.

What makes these local references different to other local references we already support (such as count.index, each.* and self.*) is that aside from the first segment, such as settings above, the rest of the address is fully dependent on interpolating the provided expression/variable inside for_each.