Support optional consequences

It's allowed in gcc and clang

fix: implement Unicode identifiers

According to cppreference, identifiers are `(XID_Start | '_')
XID_Continue*`, which is the case as of C++23 and C2x. I have confirmed
this myself with the drafts of C++23 and C2x.

https://en.cppreference.com/w/cpp/language/identifiers

Clang indeed implements identifiers as `(XID_Start | '_') XID_Continue*`
in C++ mode and C2x mode, with a slight extension to the character set
to include some extra math characters:
231992d9b8/clang/lib/Lex/Lexer.cpp (L1517-L1530)

Add an action to publish the grammar automatically

This also lets it bind to _any_ statement, which is necessary for some
c++ attributes that can attach to the statement in if, while, and
do/while statements.

Swift Package Manager

* Add support for C23 attributes

https://en.cppreference.com/w/c/language/attributes

* Use wrapper for statements with attributes to reduce state machine size

* Missed a couple _declarators that needed attributes directly after

* Use annotated_declarator for declarators that have attributes immediately following them

* Give field and type declarators the same attribute treatment

With the rise in supply chain attacks and OSS dependencies being used as a attack vector, Microsoft is working with our ecosystem partners, such as the Linux Foundation's OpenSSF, to enable OSS consumers to track packages back to their public sources.
We've identified that the following packages published to NPM do not report where sources can be found, typically accomplished by including a link to your GitHub repository in your `package.json` REPOSITORY field. This PR was created to add this value, ensuring future releases will include this provenance information.
Published NPM packages with repository information:
* tree-sitter-c

* Add support for Microsoft-specific modifiers

Microsoft-specific modifiers are keywords can be used to modify declarators to form derived types.

The specification for the modifiers themselves is here:
https://docs.microsoft.com/en-us/cpp/cpp/microsoft-specific-modifiers?view=vs-2019

* 0.16.1

* Add a rule for left part of assignment: it'll be helpful to add scoped_name_identifier (c++)

* Inline the assignment_left_expression rule

* #include can be followed by a macro name or a macro call

* In preproc_include, use preproc_call_expression

* Macro definition can contain continuation line in the argument list

* Reset grammar since line continuations are handled globally

Preserve the test.

* Parse expressions in preprocessor #if statement

* Make preproc_expression look like a normal expression

* Hide the wrapper rules
* Alias the rulres to match their corresponding expression rule
* Handle line continuations as extra tokens

Fixes #32

Fixes #31