* dotnet/master: (33 commits)
  Test dumper change to include Isimplicit/Language and some formatting change  (#22309)
  Add regression tests for fixed local function crashes (#22470)
  Use error=true in Obsolete attribute on IsByRefLikeAttribute for ref struct (#22492)
  Add tests with ref readonly and ref assemblies (#22419)
  Add test for sequence point issue with local function and conditional (#22499)
  Keep ProjectState._documentStates sorted rather than resorting the IDs
  Throttle NFW watson. (#22483)
  Suggest "in" for argument positions in IDE (#22480)
  Disable unboxing and generic conversions to/from ref-like types (#22357)
  Hold DocumentIds in ProjectState in ImmutableLists
  Fix bug in build-utils Ensure-SdkInPathAndData
  Add additional tests around Span escaping (#22413)
  Turn on the compiler server by default for the compiler VSIX (#22473)
  add 64bit detect code to razor remote host client (#22432)
  Fix a bug in escape analysis related to 'in' arguments (#22457)
  Ref must come before 'partial' in a 'ref partial struct' (#22403)
  Address PR feedback
  Ensure partial method implementation is completed when needed (#22414)
  Remove PROTOTYPE markers from "private protected" feature (#22407)
  added IVariableDeclarationStatement back to for loop's before condition (#22358)
  ...

* Adding cobyrc file for testing

* Adding isImplicit info to ioperation tests

* Adding Language name to the test dumper

* Formatting change to test dumper

* Removing cobyrc file

* Fixing more tests

* Resolving conflicts

* Moving the language to assert check

* Resolving conflicts

* Reacting to merge conflict

Fixes #21768
Fixes #22027

Reduce DocumentId array allocations

Since ImmutableDictionary and ImmutableSortedDictionary are both
implemented via trees; you can think of an ImmutableDictionary as just
being a sorted dictionary where the underlying key is the hash int.
Since our hash is just a hash of a GUID, we can compare by the GUID,
switch to a ImmutableSortedDictionary, and then avoid another sort
when we're computing checksums.

Bump NuGet monikers for the preview 1 split

There is no conversion between ref like types and either object or generic parameters (even if constrained to struct) in either direction. This change enforces that rule and adds tests around pattern matching, which exercises this rule.

We previously were using ImmutableArrays, so if you had a large number
of documents (say thousands) we'd be creating huge numbers of huge
arrays over and over again. For this pattern, ImmutableList is more
appropriate.

Fix bug in build-utils Ensure-SdkInPathAndData

Add unit tests for omitted arguments

Add unit tests for IArrayElementReferenceExpression and make the API …

Most constructs already had tests, but I added a few more just in case.
Although Span return in iterators is currently impossible because no
ref-struct capable type can be an iterator, I added a safety check in
case we allow it later.

Fixes #22305

Temporarily moves checks for `partial` back into the parser.

Fixes #22379

Fixes #18348

Fixes #22244
Related to #22406

* updated local decl

* put IVariableDeclarationStatement back to for loop before.

* put variable declaration syntax in variable declaration statement for for loop

* updated tests

* changed caller to call different APIs to create variable declaration when it can.

* changed to return IVaraibleDeclaration from CreateVariableDeclaration method

* addressed PR feedbacks

* Clean up

* Test fixes

* Fix failing test

Allow "in" at call sites as a way to request strict "in" parameter passing.