Fix pinned dotnet-watch TFMs

[tmat]

TODO: enable tests and update tests to validate 6.0 and 10.0 apps

[dotnet-policy-service]

Thanks for your PR, @@tmat.
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[Copilot]

Pull request overview

This PR fixes the pinned target framework monikers (TFMs) used by dotnet-watch components by centralizing version definitions and correcting the version threshold for selecting hot reload agent assemblies.

Changes:

• Introduces a new TargetFrameworks.props file to centralize pinned TFM definitions for hot reload agent and middleware assemblies
• Updates the threshold in HotReloadAppModel.cs from .NET 11 to .NET 10 for selecting the appropriate startup hook
• Removes the unused WatchApp60 test project

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/BuiltInTools/Watch/TargetFrameworks.props	New file defining centralized, pinned TFM versions for agent and middleware assemblies
src/BuiltInTools/Watch/RuntimeDependencies.props	Imports TargetFrameworks.props and replaces hardcoded TFMs with property references
src/BuiltInTools/Watch/AppModels/HotReloadAppModel.cs	Changes version threshold from 11 to 10 for selecting net10.0 vs net6.0 startup hook
src/BuiltInTools/HotReloadAgent/Microsoft.DotNet.HotReload.Agent.Package.csproj	Replaces hardcoded net6.0 with AgentTargetFrameworkV6 property
src/BuiltInTools/HotReloadAgent.Host/Microsoft.DotNet.HotReload.Agent.Host.Package.csproj	Replaces NetCurrent and net6.0 with AgentTargetFrameworkV10/V6 properties
src/BuiltInTools/DotNetDeltaApplier/Microsoft.Extensions.DotNetDeltaApplier.csproj	Replaces NetCurrent and net6.0 with AgentTargetFrameworkV10/V6 properties
src/BuiltInTools/BrowserRefresh/Microsoft.AspNetCore.Watch.BrowserRefresh.csproj	Replaces hardcoded net6.0 with MiddlewareTargetFrameworkV6 property
src/BuiltInTools/Web.Middleware/Microsoft.DotNet.HotReload.Web.Middleware.Package.csproj	Replaces hardcoded net6.0 with MiddlewareTargetFrameworkV6 property
test/TestAssets/TestProjects/WatchApp60/WatchApp60.csproj	Removes unused test project file
test/TestAssets/TestProjects/WatchApp60/Program.cs	Removes unused test project file