Implement fake STHAL

- Add injection attach method to middleware service
- Add Fake Hal factory, which observes framework detach,
client attach and detach, above the STHAL
- Implement a same-proc ST3 HAL, which allows for observation
and injection via a ISoundTriggerInjection
- Override default restart runnable, death listener behavior to adapt
for same-proc HAL
- Implement SoundTriggerInjection, which facades over injection client
attach/premption with a persistent injection interface.
- Add observation methods to ISoundTriggerHal and implementors to
  deliver to the injection instance

Test: Compiles
Bug: 271197938
Change-Id: I11561672bd3b4dc28d4fd158346dfa8560d97351