Project language changes edge-cases and localStore

[abcampo-iry]

Closes: https://github.com/RaspberryPiFoundation/digital-editor-issues/issues/889

This fix makes the editor reload the project when the site language changes, but only if the project has not been edited.

For example, if a project has both Spanish and English versions, switching the site from Spanish to English now loads the English project code. If the user has already changed the code, the editor keeps their local work instead of replacing it with the other language version. I've found for french is not working but i think it's because of the fallback of the server.

Screen.Recording.2026-05-27.at.12.54.18.mov

[Copilot]

Pull request overview

This PR introduces a snapshot-based “project changed” check (based on initial components) and uses it to refine two behaviors: (1) when to persist projects to localStorage on initial load, and (2) when to reload/replace the current project during locale changes, to avoid overwriting local edits.

Changes:

• Add projectHasChangedSinceInitialLoad utility (plus tests) to compare current components against an initial snapshot.
• Update useProjectPersistence to read initialComponents from Redux and avoid saving/prompting on justLoaded when the project is unchanged.
• Update useProject to avoid replacing an edited in-memory project when locale changes (plus a regression test).

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/utils/projectHelpers.js	Adds projectHasChangedSinceInitialLoad helper for snapshot-based change detection.
src/utils/projectHelpers.test.js	Adds unit tests covering unchanged/changed component scenarios.
src/hooks/useProjectPersistence.js	Uses initialComponents to skip localStorage persistence on justLoaded when unchanged.
src/hooks/useProjectPersistence.test.js	Updates persistence tests to cover the new “don’t save on justLoaded unless changed” behavior.
src/hooks/useProject.js	Adds a locale-change early-return to avoid overwriting local edits when locale differs.
src/hooks/useProject.test.js	Adds test ensuring locale changes don’t replace an edited current project.

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[Copilot]

Pull request overview

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.

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Pull request overview

Copilot reviewed 7 out of 7 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.