Fix couple of false positives in unused parameter analyzer

Merge release/dev16.2 to release/dev16.3-preview1

1. Do not flag parameters whose name has not yet been written (empty string). Fixes #36817
2. Do not flag parameters of partial method definition part. Fixes #36816

Skip BasicEditAndContinue tests

Show nullability flow analysis in Quick Info

Revert "use the source instead of the name to find nuget packages"

This reverts commit 0d8d2afb.

Fix couple of unit tests that started failing after #36566 merged fro…

Bring in last compiler changes before snap

Skip BasicEditAndContinue tests

Add only LSP server projects without liveshare dependencies.

If you mouse over a local, field, etc., and we have computed nullable
flow analysis for it, we'll tell you whether the compiler thinks the
item is null or not at that point.

Fix couple of unit tests that started failing after #36566 merged from master to release\dev16.3-preview1

Not sure why the unit test failures were not caught by the merge PR, as these tests are failing consistently in CI for PRs targeting release\dev16.3-preview1

make sure we only create OB when VS is running in IDE mode. all comma…

- Microsoft.DotNet.Arcade.Sdk - 1.0.0-beta.19326.2

Merge master to release/dev16.3-preview1

Related to #35619.

Merge master to release/dev16.3-preview1

Fix GetHashCode on constructed types with annotated type arguments

set "DeferUntilIntellisenseIsReady"=dword:00000000 for csharp and VB …

Merge master to release/dev16.3-preview1

Conflicts:
	src/Compilers/CSharp/Test/Semantic/Semantics/NullableReferenceTypesTests.cs

Handle lazy loading of analyzer command handlers

Add workarounds to IDE analyzers for missing IOperation/CFG support for using declarations

set "DeferUntilIntellisenseIsReady"=dword:00000000 for csharp and VB editor so that we opt out from VS waiting for solution load to complete

make sure we only create OB when VS is running in IDE mode. all command line mode (and all its variations) we don't need to create OB