Add Web Search (HostedWebSearchTool)

[luisquintanilla]

Ollama recently introduced hosted Web Search capabilities with an Ollama account (free tier available with higher limits for paid users)

https://ollama.com/blog/web-search

https://docs.ollama.com/web-search

Here's the current implementation in the Python SDK

https://github.com/ollama/ollama-python/blob/9ddd5f0182d0c15274e0280154231f8149e8612a/ollama/_client.py#L636-L682

Using Extensions.AI, you may be able to expose this functionality this via the HostedWebSearchTool

https://learn.microsoft.com/en-us/dotnet/api/microsoft.extensions.ai.hostedwebsearchtool?view=net-9.0-pp

https://github.com/dotnet/extensions/blob/06390edc297ba13a599edd140764b5a02bcf4e40/src/Libraries/Microsoft.Extensions.AI.Abstractions/Tools/HostedWebSearchTool.cs