859263: Add dynamic Variant switching example in Blazor Message variants documentation

[kaliraj2026]

Description

Documentation (859263): Add dynamic Variant switching example in Blazor Message variants documentation.

Issue

The Variants documentation page demonstrates only hardcoded MessageVariant values and does not include an example showing how the Variant property can be changed dynamically through C# code at runtime. This may make it difficult for users to understand how to update the message appearance based on user interactions or application state.

Solution

Added a new documentation section, "Change Variant Dynamically", that demonstrates binding the Variant property to a C# field and updating it at runtime using a SfDropDownList. This example showcases practical usage of dynamic variant switching and addresses scenarios such as user preference-based UI customization.

Code Studio usage(Mandatory)

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  • Generate new content
  • Refactor/improve existing content
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• Outcome

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Type of Change

• New documentation page
• Update to existing documentation
• Bug fix (broken links, typos, formatting issues)
• Structural change (folders, navigation, index)
• Content improvement (clarity, examples, screenshots)
• Other (please describe):

Reviewer Checklist (Mandatory)

• Reviewed the provided Code Studio usages related information
• Content changes follow UG/Documentation guidelines
• All provided information reviewed and verified
• Links and previews checked

[SyncfusionBuild]

Build Status: INPROGRESS 🔃
Build Location: 859263-messages

[SyncfusionBuild]

CI Status: SUCCESS ✅
Source Compilation: SUCCESS ✅
Build Location: 859263-messages
Technical Error(s): 0
Spelling Error(s): 0
Image Alt Text Error(s): 0
Image Size Error(s): 0
Image Name Error(s): 0
Front matter Error(s): 0
File Path Error(s): 0
CodeSnippet File Path Missing Error(s): 0
Toc Anchor Tags Validation Error(s): 0
MD Tag Validation Error(s): 0