FLUT-965287 - [Feature] Updated ug pages for treemap widget

[Hariram-SF4428]

Feature description

The task requires a comprehensive review and updating of the documentation for the Treemap widget in the "syncfusion_flutter_treemap" Flutter package. The key goals include ensuring all public APIs are documented, verifying the presence of hyperlinks, default values for properties, and trademark information, as well as correcting any misinformation.

Analysis and design

• Task ID - https://dev.azure.com/EssentialStudio/Mobile%20and%20Desktop/_workitems/edit/965287/
• Review all public APIs in the Treemap widget to confirm they are documented.
• Identify any undocumented APIs and prepare descriptions and usage examples for them.
• Check all APIs in the documentation for proper hyperlink inclusion. This ensures developers can easily reference more detailed information.
• Make sure all properties have their default values documented. This will help developers understand the initial state and expected behavior of each property.
• Ensure that trademark symbols and proper branding guidelines are followed within the documentation.
• Identify and correct any misinformation in existing documentation.

Solution description

• Compare the existing documentation with the actual APIs implemented in the Treemap widget.
• Document any missing APIs by adding their descriptions, parameters, return values, and code usage examples.
• Go through each documented API to verify if it has a hyperlink leading to further detailed API reference or related documentation. Add hyperlinks where necessary.
• Analyze the source code of the Treemap widget to extract default values of properties.
• Update documentation by clearly stating these default values next to the relevant property.
• Review the documentation for any usage of trademarks such as Syncfusion, ensuring each instance uses the correct trademark symbols as per guidelines.
• Compare the functional behavior of the Treemap widget with its documented description to identify any inaccuracies.
• Correct these inaccuracies to reflect the true behavior and properties of the widget.

Output screenshots

No, APIs explanation required for this PR, so output images needed.

Areas affected and ensured

Code snippets and content have been affected due to the modification.

API Changes

• SfTreemap: weightValueMapper missing (not explained use case individually)
• Since, it is not required to be explained individually.

Behavioral Changes

No behavioral changes due to this modification

Test cases

No test cases for this PR.

Testbed sample location

No needed for this specific task.

Does it have any known issues?

No.

Does it have memory leak?

Not applicable

MR CheckList

• Does it follow the design guidelines? It is mandatory that, we should not move the changes without reading this. Yes, followed the guidelines
• Did UI automation passed without errors? If it is customer issue, make sure it is included in the IR automation. It is a documentation related work, so not needed
• Properly working in Xamarin.Forms previewer.
• Ensured in iOS, Android, UWP and macOS (if supported). Not needed
• Have you added API comments if it is new API? Not needed
• Does it need localization? If so, update resx file in GitHub. Not needed
• Whether we have added new APIs? If so, whether it is as per the guidelines? Not needed
• If changes are made in the Xamarin.Forms sample browser project file, whether it is included in the props file too? If not, your sample level changes will not reflect in the application published in the hockey app. Not needed
• Have you ensured the changes in Android API 19 and iOS 9? Not needed

[SyncfusionBuild]

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