feat(compiler): reuse the TypeScript typecheck for template typechecking. (#19152)

This speeds up the compilation process significantly.

Also introduces a new option `fullTemplateTypeCheck` to do more checks in templates:
- check expressions inside of templatized content (e.g. inside of `<div *ngIf>`).
- check the arguments of calls to the `transform` function of pipes
- check references to directives that were exposed as variables via `exportAs`
PR Close #19152

packages/compiler/src/output/output_ast.ts

@@ -1141,8 +1141,8 @@ export function importType(
 }
 
 export function expressionType(
-    expr: Expression, typeModifiers: TypeModifier[] | null = null): ExpressionType|null {
-  return expr != null ? new ExpressionType(expr, typeModifiers) ! : null;
+    expr: Expression, typeModifiers: TypeModifier[] | null = null): ExpressionType {
+  return new ExpressionType(expr, typeModifiers);
 }
 
 export function literalArr(