feat(ivy): disable strict null checks for input bindings (#33066)

This commit introduces an internal config option of the template type
checker that allows to disable strict null checks of input bindings to
directives. This may be particularly useful when a directive is from a
library that is not compiled with `strictNullChecks` enabled.

Right now, strict null checks are enabled when  `fullTemplateTypeCheck`
is turned on, and disabled when it's off. In the near future, several of
the internal configuration options will be added as public Angular
compiler options so that users can have fine-grained control over which
areas of the template type checker to enable, allowing for a more
incremental migration strategy.

PR Close #33066

packages/compiler-cli/src/ngtsc/program.ts

@@ -401,6 +401,7 @@ export class NgtscProgram implements api.Program {
         checkQueries: false,
         checkTemplateBodies: true,
         checkTypeOfInputBindings: true,
+        strictNullInputBindings: true,
         // Even in full template type-checking mode, DOM binding checks are not quite ready yet.
         checkTypeOfDomBindings: false,
         checkTypeOfPipes: true,
@@ -412,6 +413,7 @@ export class NgtscProgram implements api.Program {
         checkQueries: false,
         checkTemplateBodies: false,
         checkTypeOfInputBindings: false,
+        strictNullInputBindings: false,
         checkTypeOfDomBindings: false,
         checkTypeOfPipes: false,
         strictSafeNavigationTypes: false,