fix(ivy): ngcc - compute potential d.ts files from .js files (#31411)

If a package delcares a class internally on an NgModule, ngcc
needs to be able to add a public export to this class's type.

Previously, if the typing file for the declared is not imported
from the typings entry-point file, then ngcc cannot find it.
Now we try to guess the .d.ts files from the equivalent .js
files.

PR Close #31411

packages/compiler-cli/ngcc/src/main.ts

@@ -154,7 +154,8 @@ export function mainNgcc(
       // the property as processed even if its underlying format has been built already.
       if (!compiledFormats.has(formatPath) && (compileAllFormats || isFirstFormat)) {
         const bundle = makeEntryPointBundle(
-            fileSystem, entryPoint, formatPath, isCore, property, format, processDts, pathMappings);
+            fileSystem, entryPoint, formatPath, isCore, property, format, processDts, pathMappings,
+            true);
         if (bundle) {
           logger.info(`Compiling ${entryPoint.name} : ${property} as ${format}`);
           const transformedFiles = transformer.transform(bundle);