A copy constructor shouldn't prevent an automatic addition of a default instance constructor for a record. (#47850)

https://github.com/dotnet/csharplang/pull/3913

* Don't offer to fix naming on positional record parameters

* Nullable enable

* Fix formatting

* Fix issue with nested constructors and parameters

* Rebase and remove ThrowIfNull

Add tests for renaming records.

Improve comments for top-level statement insertion

See #44453

Update SyntaxNodeAnalysisContext.Compilation to not return null

Initialize FatalError handlers in VS and OOP

Update Extract Method to support top-level statements

* Use MessagePack for ISB serialization

* DocumentHighlighting service

* Renamer, EncapsulateField, TupleToStruct services

* SymbolFinder and FindUsages services

* NavigateToSearch service

* FindUsages, References fixes

* AddImport service

* SymbolSearchUpdate service

* ExtensionMethodImportCompletion service

* DependentTypeFinder service

* GlobalNotificationDelivery service

* CodeLensReferences service

* Remove CodeAnalysis service

* Remove unused code

* Fix warnings.

* Remove unused

* Error reporting and logging

* Update StreamJsonRpc to 2.6.86-alpha

* Improve callback error handling.

* Update Watson reporting

* PR feedback

* Fix tests

* Fixes

* Remove unused field

* Rename shutdown service

* Switch diagnostic serialization from ObjectReader/Writer serializer to MessagePack

* Fix diagnostic reporting issue in ASP.NET apps

Change hang to blocking

Support category-based exclusions in user option for unnecessary supp…

Fix issues with opening source generated files

Allow genearted local function parameter name to shadow variables

Some more error list performance improvements

Source Generators always run now.

I passed the span to navigate to along to the service, and then never
used it. Oops.

This factory service was only being used to ensure there's a singleton
across all workspaces, but that can be just as easily done by exporting
it directly.

If the file is already open, then this was causing us to trigger a
reload prompt which we don't want.

Move to .NET 5 Preview 8 SDK