Sync editor pin to v4.0.3

[github-actions]

The editor published v4.0.3. This updates .editor-version and the playground blueprint pin.

To ship a plugin release bundling this editor, follow the release-preparation flow (DEVELOPMENT.md, "Versioning and releases"): commit the final version.php, merge, tag that commit, and publish the release — release.yml builds the ZIP from the tag.

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Moodle Playground Preview

The changes in this pull request can be previewed and tested using a Moodle Playground instance.

ℹ️ The eXeLearning editor is fetched from the shared release and unpacked into the plugin when the playground boots, so the first load may take a few extra seconds. ELPX upload, viewer and preview work normally.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.31%. Comparing base (a232775) to head (85ae256).
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff            @@
##               main     #117   +/-   ##
=========================================
  Coverage     92.31%   92.31%           
  Complexity      824      824           
=========================================
  Files            51       51           
  Lines          3734     3734           
=========================================
  Hits           3447     3447           
  Misses          287      287           

Flag	Coverage Δ
javascript	94.11% <ø> (ø)
php	92.23% <ø> (ø)

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Components	Coverage Δ
PHP (server-side)	92.23% <ø> (ø)
JavaScript (SCORM tracker)	94.11% <ø> (ø)

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