docs: TabBar Styling Docs

[vatsashah45]

GitHub Issue (If applicable):
closes https://github.com/unoplatform/uno.ai-private/issues/500
closes https://github.com/unoplatform/uno.ai-private/issues/501

PR Type

What kind of change does this PR introduce?

• Documentation content changes

What is the current behavior?

What is the new behavior?

PR Checklist

Please check if your PR fulfills the following requirements:

• Tested code with current supported SDKs
• Tested the changes where applicable:
  • UWP
  • WinUI
  • iOS
  • Android
  • WASM
  • MacOS
• Updated the documentation as needed:
  • General Doc Update
  • Controls Doc Update
  • Extensions Doc Update
  • controls-styles.md
  • lightweight-styling.md (LightWeight Styling Resource Keys)
• Runtime Tests and/or UI Tests for the changes have been added (for bug fixes / features) (if applicable)
• Contains NO breaking changes
• Associated with an issue (GitHub or internal)
• Commits must be following the Conventional Commits specification.

[Copilot]

Pull request overview

This PR updates TabBar documentation to clarify the correct styling pattern for Material Toolkit v2. The changes address confusion about how to apply styles to TabBar components by emphasizing that styles should be applied to the TabBar container rather than individual TabBarItem elements.

Key Changes:

• Updated code examples to demonstrate applying styles to TabBar containers (e.g., BottomTabBarStyle) instead of individual TabBarItem elements
• Added IMPORTANT callout boxes explaining the Material Toolkit v2 styling pattern
• Clarified that BottomTabBarItemStyle and VerticalTabBarItemStyle are internal implementation details that should not be referenced directly

Reviewed changes

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

File	Description
doc/controls/walkthroughs/TabBar-and-TabBarItem.howto.md	Updated badge examples and added important note about applying styles to TabBar container instead of TabBarItem elements
doc/controls/TabBarAndTabBarItem.md	Added comprehensive IMPORTANT callout explaining the Material Toolkit v2 styling pattern, updated badge examples to follow the pattern, and clarified exception for BottomFabTabBarItemStyle

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[unodevops]

⚠️⚠️ The build 187086 has failed on Uno Toolkit - CI.

[Copilot]

Pull request overview

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

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[unodevops]

⚠️⚠️ The build 187093 has failed on Uno Toolkit - CI.