Add turndown and turndown-plugin-gfm dependencies

[PavithragokulakrishnanSF]

Feature description

Add turndown and turndown-plugin-gfm dependencies to make the sample browser runnable

Requirement and specification document

• API Review (Task link: _________________)
• Azure Task with detailed feature information ()
• Not applicable

Feature scope and impact

• Core functionality (high impact)
• Enhancement to existing feature
• New standalone feature
• Experimental feature

Code Studio usage(Mandatory)

• Code Studio used in this PR/MR?

  • Yes
  • No

• If Yes: Primary use (choose one)

  • Generate new code
  • Refactor/improve existing code
  • Tests
  • Bug fix / debugging help
  • Docs / comments
  • Review assistance (explanations/summaries)
  • Other:

• Outcome

  • Saved time
  • Neutral
  • Cost time

• If “Cost time” explain in short (1 or 2 lines):

Output screenshots/demos

Post the output screenshots or demo links if UI is affected or added.

Feature matrix documentation

• Feature matrix document updated Centralized location
• Not applicable

Testing coverage

• Tested against feature matrix
• Edge cases and error scenarios verified
• Cross-browser testing completed

Test cases and automation

• Test cases documented and attached to this PR
• BUnit tests added (PR link: _________________)
• Playwright tests added (PR link: _________________)
• Manual testing only (justification: _________________)
• Not applicable

Test bed sample location

Provide the test bed sample location for code reviewers to verify the feature's behavior.

Platform verification

• Verified in Blazor Server
• Verified in Blazor WASM
• Not applicable

Related components

• Feature applicable to other components (Tasks created: _________________) (tagged "needs-attention-coreteam")
• Not applicable to other components

Breaking changes

• Contains breaking changes - provide migration guidance (added "breaking-change" label)
• No breaking changes

Performance verification

• Memory usage verified (no leaks)
• Rendering performance verified
• Not applicable

Reviewer Checklist

• Reviewed the provided Code Studio usages related information.
• Feature matrix documentation verified
• Test coverage verified
• Sample implementation reviewed
• Code meets standards and best practices
• C# implementation used appropriately (minimal JavaScript)