compiler: Refactor Compiler To Remove Ambiguities

There were significant overlaps in the names of data structures
between the compiler and the language that made it necessary
to litter the code with P4Lang.xxxx. This refactor removes that
requirement in most places (Parser is ambiguous wherever TreeSitter
is used -- cannot avoid that!)

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>

Sources/P4Runtime/Parser.swift

@@ -66,7 +66,7 @@ extension ParserStateDirectTransitionValue: EvaluatableParserState {
     return false
   }
 
-  public func state() -> P4Lang.ParserState {
+  public func state() -> ParserState {
     return self.state
   }
 }
@@ -82,7 +82,7 @@ extension ParserStateNoTransitionValue: EvaluatableParserState {
     return true
   }
 
-  public func state() -> P4Lang.ParserState {
+  public func state() -> ParserState {
     return self.state
   }
 }
@@ -125,7 +125,7 @@ extension ParserStateSelectTransitionValue: EvaluatableParserState {
     return false
   }
 
-  public func state() -> P4Lang.ParserState {
+  public func state() -> ParserState {
     return self.state
   }
 }
@@ -134,7 +134,7 @@ extension ParserValue: LibraryCallable {
   public typealias T = InstantiatedParserState
   public func call(
     execution: Common.ProgramExecution, arguments: ArgumentList
-  ) -> (P4Lang.InstantiatedParserState, Common.ProgramExecution) {
+  ) -> (InstantiatedParserState, Common.ProgramExecution) {
     var execution = execution.enter_scope()
 
     execution = execution.declare(