perf(tsc): support vue files with project reference delcaration

Support vue files with project reference output, so that typescript
resolves the project reference vue file as the output `vue.d.ts` file
rather than the source.

This drastically improves performance in large projects that have vue
files imported from project references. As much as 50% performance
improvements as ts no longer recompiles vue files from source.

Setup the real path to pass back the real path of vue files, as they
are virtual files the inbuilt realpath always returns the non symlinked
version (node_modules), which affects DX with vue-tsc as errors
originating from upstream project reference packages are returned
with the node modules path rather than the source. This change is also
required to power the usage of `d.ts` files.

packages/tsc/src/index.ts

@@ -64,7 +64,7 @@ export function createProgram(options: ts.CreateProgramOptions) {
 			modifiedTime: number,
 			scriptSnapshot: ts.IScriptSnapshot,
 		}>();
-		const languageHost: vue.TypeScriptLanguageHost = {
+		const languageHost: vue.TypeScriptLanguageHost & Partial<ts.LanguageServiceHost> = {
 			workspacePath: ctx.options.host!.getCurrentDirectory().replace(windowsPathReg, '/'),
 			rootPath: ctx.options.host!.getCurrentDirectory().replace(windowsPathReg, '/'),
 			getCompilationSettings: () => ctx.options.options,
@@ -77,6 +77,20 @@ export function createProgram(options: ts.CreateProgramOptions) {
 			},
 			getProjectReferences: () => ctx.options.projectReferences,
 			getCancellationToken: ctx.options.host!.getCancellationToken ? () => ctx.options.host!.getCancellationToken!() : undefined,
+			realpath(path) {
+				const realpath = ctx.options.host!.realpath! ?? ts.sys.realpath
+				const match = /^(?<path>.+\.vue)\.(?<extension>.+)$/.exec(path)
+				return match?.groups ? `${realpath(match.groups.path)}.${match.groups.extension}` : realpath(path)
+			},
+			getParsedCommandLine: (path) => {
+				const possibleExtensions = ['ts', 'tsx']
+				const commandLine = ts.getParsedCommandLineOfConfigFile(path, undefined, ts.sys as any)
+				if (!commandLine) return undefined 
+				return { 
+					...commandLine, 
+					fileNames: commandLine.fileNames.flatMap(name => name.endsWith('.vue') ? possibleExtensions.map(ext => `${name}.${ext}`) : [name])
+				}
+			},
 		};
 		const languageContext = vue.createLanguageContext(
 			languageHost,