[Workers][Developer Platform] Add "Workers Platform" roles to "roles.mdx" (cloudflare#22362)

* feat: add "Workers Platform (Read-only)" role

The role should provide read-only access to most Workers Platform
products:

https://www.cloudflare.com/developer-platform/products/

These include:

- Workers
- Pages
- Durabe Objects
- KV
- R2
- etc

* feat: rename role "Cloudflare Workers Admin" to "Workers Platform Admin"

The former was not even the latest name, it was "Workers Admin". So the
roles for this role were a bit out of date.

* feat: add changelog entry for "Workers Platform" roles

* Update 2025-06-16-workers-platform-admin-role.mdx

* Update 2025-06-16-workers-platform-admin-role.mdx

---------

Co-authored-by: Brendan Irvine-Broque <[email protected]>

Author: 2 people

src/content/changelog/workers/2025-06-16-workers-platform-admin-role.mdx

@@ -0,0 +1,17 @@
+---
+title: Grant account members read-only access to the Workers Platform
+description: You can now grant members of your Cloudflare account read-only access to the Workers Platform.
+date: 2025-06-16T00:00:00Z
+---
+
+You can now grant members of your Cloudflare account read-only access to the Workers
+Platform.
+
+The new "Workers Platform (Read-only)" role grants read-only access to all products typically used as part of Cloudflare's Developer Platform, including [Workers](/workers/), [Pages](/pages/), [Durable Objects](/durable-objects/), [KV](/kv/), [R2](/r2/), Zones, [Zone Analytics](/analytics/account-and-zone-analytics/zone-analytics/) and [Page Rules](/rules/). When Cloudflare introduces new products to the Workers platform, we will add additional read-only permissions to this role.
+
+Additionally, the role previously named "Workers Admin" has been renamed to "Workers Platform Admin". This
+change ensures that the name more accurately reflects the permissions granted — this
+role has always granted access to more than just
+Workers — it grants read and write access to the products mentioned above, and similarly, as new products are added to the Workers platform, we will add additional read and write permissions to this role.
+
+You can review the updated roles in the [developer docs](/fundamentals/manage-members/roles/).