chore(cli): release 5.20.0

Author: github-actions[bot]

…hanges/unreleased/add-check-fix-flag.yml …li/changes/5.20.0/add-check-fix-flag.ymlpackages/cli/cli/changes/unreleased/add-check-fix-flag.yml renamed to packages/cli/cli/changes/5.20.0/add-check-fix-flag.yml packages/cli/cli/changes/unreleased/add-check-fix-flag.yml renamed to packages/cli/cli/changes/5.20.0/add-check-fix-flag.yml

@@ -1,4 +1,14 @@
 # yaml-language-server: $schema=../../../fern-versions-yml.schema.json
+- version: 5.20.0
+  changelogEntry:
+    - summary: |
+        Add `--fix` flag to `fern check`, `fern sdk check`, and `fern docs check`.
+        When specified, the CLI automatically applies known fixes for detected issues
+        (e.g. replacing invalid SDK target versions with the latest stable release,
+        applying deterministic MDX parse error fixes).
+      type: feat
+  createdAt: "2026-05-07"
+  irVersion: 66
 - version: 5.19.1
   changelogEntry:
     - summary: |