Reorganize CMSObject removals

[laoneo]

User description

Manual entry for pr joomla/joomla-cms#44880.

Followup of #380.

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PR Type

Documentation

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Description

• Documented the removal of CMSObject class usage.

• Explained transition from CMSObject to stdClass.

• Highlighted affected components and models in Joomla core.

• Provided examples for adapting to the changes.

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Changes walkthrough 📝

	Relevant files
Documentation	removed-backward-incompatibility.md Documented removal of `CMSObject` and transition to `stdClass` migrations/54-60/removed-backward-incompatibility.md Added detailed documentation on CMSObject removal. Explained the transition to stdClass in core models. Provided examples for replacing CMSObject functions. Highlighted affected components and their adjustments. +49/-44

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PR Reviewer Guide 🔍

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⏱️ Estimated effort to review: 2 🔵🔵⚪⚪⚪

🧪 No relevant tests

🔒 No security concerns identified

⚡ Recommended focus areas for review Documentation Clarity The documentation should clarify whether existing extensions need to be updated to handle both CMSObject and stdClass during the transition period for backward compatibility - Description: The `AdminModel` class does return a `stdClass` object in the `getItem` function instead of a `CMSObject`. This means that all the deprecated functions of `CMSObject` are not available anymore. Mainly the set and get function should be replaced accordingly as documented in the `CMSObject` class or the respective traits. For example you can use ```php

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PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Impact
General	Add type safety warning Add a warning note about potential data type issues when accessing properties of stdClass objects, since they don't enforce type safety like CMSObject did. Developers should implement their own type checking when needed. migrations/54-60/removed-backward-incompatibility.md [18-22] #### getItem returns a stdClass instead of CMSObject - PR: https://github.com/joomla/joomla-cms/pull/42961 - File: libraries/src/MVC/Model/AdminModel.php -- Description: The `AdminModel` class does return a `stdClass` object in the `getItem` function instead of a `CMSObject`. +- Description: The `AdminModel` class does return a `stdClass` object in the `getItem` function instead of a `CMSObject`. Note that stdClass objects don't enforce property types - developers should implement appropriate type checking when accessing properties if type safety is required. [To ensure code accuracy, apply this suggestion manually] Suggestion importance[1-10]: 8 __ Why: The suggestion addresses an important security and reliability concern by warning developers about the loss of type safety when migrating from CMSObject to stdClass. This is crucial information for maintaining code quality and preventing potential runtime errors.	Medium