Previously, `ReferenceEmitter.emit()` took an `ImportMode` enum value, where
one value of the enum allowed forcing new imports to be generated when
emitting a reference to some value or type.
This commit refactors `ImportMode` to be an `ImportFlags` value instead.
Using a bit field of flags will allow future customization of reference
emitting.
PR Close#34649
The `ModuleWithProviders` type has an optional type parameter that
should be specified to indicate what NgModule class will be provided.
This enables the Ivy compiler to statically determine the NgModule type
from the declaration files. This type parameter will become required in
the future, however to aid in the migration the compiler will detect
code patterns where using `ModuleWithProviders` as return type is
appropriate, in which case it transforms the emitted .d.ts files to
include the generic type argument.
This should reduce the number of occurrences where `ModuleWithProviders`
is referenced without its generic type argument.
Resolves FW-389
PR Close#34235
