Port Hot Reload changes from main

[tmat]

Port #49611 and #49974 from main

[github-actions]

This PR is targeting main, which is now for .NET 11-facing work. If you intended to target .NET 10, either retarget this PR to release/10.0.1xx or make sure you backport the change to release/10.0.1xx after merging. See #50394 for more details.

[dotnet-policy-service]

Thanks for your PR, @@tmat.
To learn about the PR process and branching schedule of this repo, please take a look at the SDK PR Guide.

[tmat]

@DustinCampbell @phil-allen-msft ptal.

[Copilot]

Pull Request Overview

This pull request ports Hot Reload changes from main to align the test infrastructure with the main branch implementation. The changes primarily focus on modernizing the logging and reporting architecture by migrating from a custom IReporter interface to the standard Microsoft.Extensions.Logging framework.

Key Changes:

• Replace custom IReporter interface with ILogger and ILoggerFactory from Microsoft.Extensions.Logging
• Update test utilities to use the new logging infrastructure while maintaining backward compatibility for testing
• Modernize message descriptors and error handling patterns

Reviewed Changes

Copilot reviewed 109 out of 109 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
test/dotnet-watch.Tests/Watch/*.cs	Updated test context creation to use new logging infrastructure
test/dotnet-watch.Tests/TestUtilities/*.cs	Migrated test utilities from reporter-based to logger-based patterns
test/dotnet-watch.Tests/HotReload/*.cs	Updated Hot Reload tests to use new API methods and message patterns
src/BuiltInTools/dotnet-watch/UI/*.cs	Replaced IReporter with ILogger and modernized message handling
src/BuiltInTools/dotnet-watch/Process/*.cs	Updated process management to use structured logging
src/BuiltInTools/dotnet-watch/HotReload/*.cs	Migrated Hot Reload components to use ILogger