feat: Add boundary_role data source (#743)

docs/data-sources/role.md

@@ -0,0 +1,62 @@
+---
+# generated by https://github.com/hashicorp/terraform-plugin-docs
+page_title: "boundary_role Data Source - terraform-provider-boundary"
+subcategory: ""
+description: |-
+  The boundary_role data source allows you to find a Boundary role.
+---
+
+# boundary_role (Data Source)
+
+The boundary_role data source allows you to find a Boundary role.
+
+## Example Usage
+
+```terraform
+# Role from the global scope
+data "boundary_role" "global_role" {
+  name = "global_role_one"
+}
+
+# Role from an org scope
+data "boundary_scope" "org" {
+  name     = "org_one"
+  scope_id = "global"
+}
+
+data "boundary_role" "org_role" {
+  name     = "org_role_one"
+  scope_id = data.boundary_scope.org.id
+}
+```
+
+<!-- schema generated by tfplugindocs -->
+## Schema
+
+### Required
+
+- `name` (String) The name of the role to retrieve.
+
+### Optional
+
+- `scope_id` (String) The scope ID in which the resource is created. Defaults `global` if unset.
+
+### Read-Only
+
+- `description` (String) The description of the retrieved role.
+- `grant_scope_ids` (Set of String) The list of scope IDs for the role's grants.
+- `grant_strings` (Set of String) The list of stringified grants for the role.
+- `id` (String) The ID of the retrieved role.
+- `principal_ids` (Set of String) The list of principal (user or group) IDs added as principals on the role.
+- `scope` (List of Object) (see [below for nested schema](#nestedatt--scope))
+
+<a id="nestedatt--scope"></a>
+### Nested Schema for `scope`
+
+Read-Only:
+
+- `description` (String)
+- `id` (String)
+- `name` (String)
+- `parent_scope_id` (String)
+- `type` (String)