docs: update docs based on recent fern-platform commits (2026-05-20) (#5572)

Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>
Co-authored-by: bot_apk <apk@cognition.ai>
Co-authored-by: Devin Logan <devinannlogan@gmail.com>

Author: 4 people

fern/products/dashboard/pages/changelog/2026-05-20.mdx

@@ -0,0 +1,9 @@
+---
+tags: ["security"]
+---
+
+## Preview site deletion for all org members
+
+Any organization member can delete preview docs sites from the Dashboard. Deleting production docs sites still requires Admin permissions.
+
+<Button intent="none" outlined rightIcon="arrow-right" href="/learn/dashboard/configuration/permissions">Read the docs</Button>

fern/products/dashboard/pages/permissions.mdx

@@ -74,9 +74,11 @@ Viewers have read-only access to the Dashboard (settings, analytics) and can dep
 | Manage members                | Yes   | No                   | No     |
 | Add or update a custom domain | Yes   | No                   | No     |
 | Manage password protection    | Yes   | No                   | No     |
+| Delete production docs sites  | Yes   | No                   | No     |
 | View dashboard and analytics  | Yes   | Yes                  | Yes    |
 | Publish to production         | Yes   | Configure per Editor | No     |
 | Deploy previews               | Yes   | Yes                  | Yes    |
+| Delete preview docs sites     | Yes   | Yes                  | Yes    |
 | Generate locally              | Yes   | Yes                  | Yes    |
 | Use Fern Editor               | Yes   | Yes                  | No     |