Implement CallingAccountSelector and AssistedDialAction

CallingAccountSelector examines the CallIntentBuilder, and if the PhoneAccountHandle is missing on a multi-SIM device while the default is not set, it will show a dialog to let the user select it. This step used to be after the in call UI is launched and telecom wants dialer to disambiguate. This step is moved to pre call as dialer need more control, like voicemail calls should always prompt, or the preferred SIM info might be available. This also allows telecom to send the selected PhoneAccountHandle to other apps so they have more information on how to rewrite numbers.

AssistedDialAction replaces the step previously in CallIntentBuilder.build(), and rewrites the URI.

Pre-call actions are not hooked up for dialing in this CL yet, assisted dialing will still be broken.

Bug: 64216442
Test: CallingAccountSelectorTest, AssistedDialActionTest
PiperOrigin-RevId: 174917321
Change-Id: Iba2e9092f83c036b402d4044a48ff5c44e806210