Update ModelContextProtocol to latest

[stephentoub]

Updates to the latest build of ModelContextProtocol and related assemblies.

[Copilot]

Pull request overview

This PR updates the ModelContextProtocol and related Microsoft.Extensions packages to their latest versions (0.4.1-preview.1 and 10.0.0 respectively), adapting the codebase to breaking API changes in the updated libraries.

• Updated 15+ package dependencies to latest versions
• Adapted to ModelContextProtocol's API changes from IReadOnlyDictionary to IDictionary for tool arguments
• Updated sampling API to use collection-based content model with required MaxTokens property

Reviewed changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 10 comments.

Show a summary per file

File	Description
Directory.Packages.props	Updates package versions for ModelContextProtocol (0.4.1-preview.1), Microsoft.Extensions.* (10.0.0), System.* (10.0.0), and Azure AI packages
core/Azure.Mcp.Core/src/Commands/CommandExtensions.cs	Changes method signatures from IReadOnlyDictionary to IDictionary to match updated ModelContextProtocol API
core/Azure.Mcp.Core/src/Areas/Server/Commands/ToolLoading/BaseToolLoader.cs	Updates parameter type from IReadOnlyDictionary to IDictionary for API compatibility
core/Azure.Mcp.Core/src/Areas/Server/Commands/ToolLoading/RegistryToolLoader.cs	Changes private method signature to accept IDictionary instead of IReadOnlyDictionary
core/Azure.Mcp.Core/src/Areas/Server/Commands/ToolLoading/NamespaceToolLoader.cs	Updates method signatures and adds required MaxTokens property; converts content to collection-based model
core/Azure.Mcp.Core/src/Areas/Server/Commands/ToolLoading/ServerToolLoader.cs	Adds MaxTokens property and updates content model to use collections; updates content access pattern
core/Azure.Mcp.Core/src/Areas/Server/Commands/ToolLoading/SingleProxyToolLoader.cs	Adds MaxTokens property to sampling requests and updates content handling to collection-based API (2 locations)
core/Azure.Mcp.Core/tests/Azure.Mcp.Core.UnitTests/Areas/Server/Commands/ToolLoading/BaseToolLoaderTests.cs	Updates test to match new API: adds MaxTokens property and converts content to collection syntax
core/Azure.Mcp.Core/tests/Azure.Mcp.Core.UnitTests/Areas/Server/Commands/ToolLoading/ServerToolLoaderTests.cs	Updates test helper method signature from IReadOnlyDictionary to IDictionary
core/Azure.Mcp.Core/tests/Azure.Mcp.Core.UnitTests/Areas/Server/Commands/ToolLoading/RegistryToolLoaderTests.cs	Updates test helper method signature from IReadOnlyDictionary to IDictionary
core/Azure.Mcp.Core/tests/Azure.Mcp.Core.UnitTests/Areas/Server/Commands/ToolLoading/CompositeToolLoaderTests.cs	Updates test helper method signature from IReadOnlyDictionary to IDictionary
core/Azure.Mcp.Core/tests/Azure.Mcp.Core.UnitTests/Areas/Server/Commands/Runtime/McpRuntimeTests.cs	Updates test helper method signature from IReadOnlyDictionary to IDictionary

[stephentoub]

Waiting on #1221...

[joshfree]

#1221 has a number of issues we have to work through with new AOT/Trimming errors that don't reproduce on the current 10-RC build we shipped with.

It'll be a few days.