Changelog for v0.40.0-preview.3 (#25904)

Co-authored-by: gemini-cli-robot <224641728+gemini-cli-robot@users.noreply.github.com>
Co-authored-by: g-samroberts <samroberts@google.com>
Co-authored-by: Sam Roberts <158088236+g-samroberts@users.noreply.github.com>

Author: gemini-cli-robot

docs/changelogs/preview.md

@@ -1,6 +1,6 @@
-# Preview release: v0.40.0-preview.2
+# Preview release: v0.40.0-preview.3
 
-Released: April 23, 2026
+Released: April 24, 2026
 
 Our preview release includes the latest, new, and experimental features. This
 release may not be as stable as our [latest weekly release](latest.md).
@@ -30,6 +30,12 @@ npm install -g @google/gemini-cli@preview
 
 ## What's Changed
 
+- update FatalUntrustedWorkspaceError message to include doc link by @ehedlund
+  in [#25874](https://github.com/google-gemini/gemini-cli/pull/25874)
+- feat(core): enhance shell command validation and add core tools allowlist by
+  @galz10 in [#25720](https://github.com/google-gemini/gemini-cli/pull/25720)
+- feat(cli): secure .env loading and enforce workspace trust in headless mode by
+  @ehedlund in [#25814](https://github.com/google-gemini/gemini-cli/pull/25814)
 - chore(release): bump version to 0.40.0-nightly.20260414.g5b1f7375a by
   @gemini-cli-robot in
   [#25420](https://github.com/google-gemini/gemini-cli/pull/25420)
@@ -398,4 +404,4 @@ npm install -g @google/gemini-cli@preview
   [#25336](https://github.com/google-gemini/gemini-cli/pull/25336)
 
 **Full Changelog**:
-https://github.com/google-gemini/gemini-cli/compare/v0.38.0-preview.0...v0.40.0-preview.2
+https://github.com/google-gemini/gemini-cli/compare/v0.38.0-preview.0...v0.40.0-preview.3