fix(iam_policy_project): set RegionType=Global to use the global IAM endpoint

[cofyc]

Summary

The ReadResource for volcengine_iam_policy_project (added in v0.0.189) omits RegionType, so it falls through to RegionType: Regional (zero value of the iota-based enum). The Universal client then routes the call to a regional IAM endpoint (e.g. iam.cn-shanghai.volcengineapi.com) instead of the global one (iam.volcengineapi.com).

In practice every Read fails with the cryptic transport error:

Error: error on reading resource "UserGroup:<group>:System:<policy>:<project>",
RequestError: send request failed

Every read errors → every plan errors → resource is unusable. This blocks importing existing project-scoped attachments and prevents drift detection on managed ones.

Reproduction

terraform {
  required_providers {
    volcengine = {
      source  = "volcengine/volcengine"
      version = "0.0.196"
    }
  }
}

provider "volcengine" {
  region = "cn-shanghai"
}

# An existing project-scoped UserGroup policy attachment.
import {
  to = volcengine_iam_policy_project.example
  id = "UserGroup:my_group:System:ArkFullAccess:my_project"
}

resource "volcengine_iam_policy_project" "example" {
  principal_type = "UserGroup"
  principal_name = "my_group"
  policy_type    = "System"
  policy_name    = "ArkFullAccess"
  project_names  = ["my_project"]
}

terraform plan returns:

Error: error on reading resource "UserGroup:my_group:System:ArkFullAccess:my_project", RequestError: send request failed

Fix

One line — add RegionType: ve.Global to the inline UniversalInfo. After the patch the same plan succeeds with 0 to add, 0 to change, 0 to destroy and the resource is correctly imported.

Every other IAM resource in this provider that calls ListAttachedUserGroupPolicies (e.g. iam_user_group_policy_attachment's getUniversalInfo helper) already sets RegionType: ve.Global — this fix just brings iam_policy_project in line with the rest.

Test plan

• Built locally and ran terraform plan against a real Volcengine account in cn-shanghai with 15 existing project-scoped UserGroup attachments.
• Without the patch: 15 reads, all fail with RequestError: send request failed.
• With the patch: 15 reads succeed, plan reports 0 to add, 0 to change, 0 to destroy.

[cofyc]

cc @stackend