feat(ivy): exclude declarations from injector imports (#29598)

Prior to this change, a module's imports and exports would be used verbatim
as an injectors' imports. This is detrimental for tree-shaking, as a
module's exports could reference declarations that would then prevent such
declarations from being eligible for tree-shaking.

Since an injector actually only needs NgModule references as its imports,
we may safely filter out any declarations from the list of module exports.
This makes them eligible for tree-shaking once again.

PR Close #29598

integration/_payload-limits.json

@@ -21,7 +21,7 @@
     "master": {
       "uncompressed": {
         "runtime": 1440,
-        "main": 212976,
+        "main": 155609,
         "polyfills": 43567
       }
     }