Group all NuGet packages in Dependabot updates

[Copilot]

Dependabot was creating separate PRs for different NuGet package categories (analyzers, test dependencies, and ungrouped packages like SourceLink). This consolidates all NuGet updates into a single weekly PR.

Changes

• Replaced separate analyzers and test-dependencies groups with single nuget-dependencies group using wildcard pattern *
• All NuGet packages now update together regardless of type

Configuration

groups:
  nuget-dependencies:
    patterns:
      - "*"

This reduces PR volume from potentially 3+ separate NuGet PRs to 1 consolidated PR per week.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>[Feature]:</issue_title>
<issue_description>### Problem Statement

Dependabot creates too many separate pull requests.

Proposed Solution

Group all nuget packages into a single group.

Alternatives Considered

No response

Usage Examples

N/A

Benefits

Easier maintenance

Priority

Medium - Would improve my workflow

Willingness to Contribute

Yes, I can submit a pull request

Additional Context

No response

Checklist

• I have searched existing issues to ensure this is not a duplicate
• I have provided a clear description of the feature
• I have explained why this feature would be useful</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes [Feature]: #36

---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.