Event-based CMS resolver extensibility

[MartinKrzykawski]

This pull request adds a detailed explanation to the CMS element extensibility documentation, focusing on how to modify entity data before it is rendered in Shopware's CMS system. The new section clarifies the event-based extension points available for developers and provides a practical example of subscribing to CMS slot resolution events to alter product data before it is displayed.

Event-based extensibility documentation:

• Added a comprehensive overview of Shopware’s CMS slot resolution pipeline, explaining why entity modifications after page load events do not affect CMS output and where developers should intervene for effective data changes.
• Documented the three main CMS extension classes (CmsSlotsDataCollectExtension, CmsSlotsDataEnrichExtension, and CmsSlotsDataResolveExtension) and their lifecycle event hooks (.pre and .post), including typical use cases.

Practical guidance and example:

• Included a step-by-step workflow for subscribing to CMS slot resolution events and modifying product properties before rendering.
• Provided a simplified PHP example of an event subscriber (CmsPreResolveSubscriber) that demonstrates how to intercept and modify a ProductEntity during the CMS slot resolution process.

[Copilot]

Pull request overview

This PR adds comprehensive documentation about event-based extensibility for CMS resolver customization. It explains how developers can use Shopware's CMS extension point events to modify entity data before it's copied into CMS elements during the slot-resolution process.

• Documents three new CMS extension classes: CmsSlotsDataCollectExtension, CmsSlotsDataEnrichExtension, and CmsSlotsDataResolveExtension
• Provides a workflow and PHP example for intercepting CMS resolution events
• Explains why modifications must happen during CMS resolution rather than after page loading

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.