fix: prevent stale companion controls after teardown

[papi-ux]

Summary

Prevents stale Nova companion controls from surviving or reopening after stream teardown.

• marks the stream inactive before asynchronous teardown begins;
• synchronously dismisses the companion notification and Presentation when streaming stops;
• dispatches delayed display/notification reopen requests to the UI thread;
• re-evaluates the live stream/activity lifecycle tuple at execution time;
• blocks companion controls when the stream is inactive or Game is finishing/destroyed;
• preserves partial-Presentation cleanup and API 21 compatibility.

Lifecycle contract

CompanionControlLifecyclePolicy.canShow(...) allows companion controls only when all three live conditions hold:

isStreamActive == true
isFinishing() == false
isDestroyed == false

The decision is made on the UI thread when the queued reopen callback executes, rather than using stale state captured when the request was queued.

Verification

Reviewed commit:

093605e237773d63259e4c3f79247991bb09e045

Exact reviewed binary-diff SHA-256:

3b2739cc670d169c3bab4d1628aaa42824fd481533b8bf18bb2ea48dfe50a228

Base/current origin/master at freeze:

481e2eb5c42904690bc3164aa4b6a8a94801f432

Fresh pc-papi gates:

• Root JVM suite: 786/786 passed
• Non-root JVM suite: 780/780 passed
• Helper/onboarding suite: 51/51 passed
• Root fail-on-error lint: passed
• Non-root fail-on-error lint: passed
• ARM64 unsigned release APK assembly: passed
• ARMv7 unsigned release APK assembly: passed
• x86_64 unsigned release APK assembly: passed
• Live-tuple-to-permissive-constants compiling mutation: RED
• Restored focused lifecycle source guard: GREEN
• Added-production-line security/privacy scan: 0 findings
• Fresh exact-hash fail-closed review: passed with no blockers
• Post-commit diff reproduced the exact reviewed SHA-256

Unsigned APK metadata:

ABI	Package	Version	Version code
arm64-v8a	com.papi.nova	1.3.1	33
armeabi-v7a	com.papi.nova	1.3.1	33
x86_64	com.papi.nova	1.3.1	33

Scope boundary

This PR does not install an APK, claim Retroid/Thor hardware validation, publish a release, or deploy/restart Polaris. Physical Thor remains a separate v1.3.2 release gate.