.NET: Bump Microsoft.Agents.AI.Workflows from 1.0.0-preview.251125.1 to 1.0.0-preview.251219.1#2997

crickman merged 3 commits intomainmicrosoft/agent-framework:mainfrom

dependabot/nuget/dotnet/samples/HostedAgents/AgentsInWorkflows/Microsoft.Agents.AI.Workflows-1.0.0-preview.251219.1microsoft/agent-framework:dependabot/nuget/dotnet/samples/HostedAgents/AgentsInWorkflows/Microsoft.Agents.AI.Workflows-1.0.0-preview.251219.1Copy head branch name to clipboard