fix(nova): route dual-screen controls to companion display

[papi-ux]

Summary

Refs #115. Builds on the display-target selector from #98/#106.

• Derives a separate companion/control display from the actual Android stream display.
• Routes ExternalDisplayControlActivity to the non-stream companion display instead of hard-coding Display.DEFAULT_DISPLAY.
• Starts companion controls even when the stream is on the primary/default display, which is the Thor Largest / This device screen path.
• Splits stream bootstrapping into a dedicated GameDisplayLaunchTrampolineActivity so the singleton companion-control activity no longer doubles as a launch trampoline.
• Forces stream launch/relaunch onto the requested Android display, including Display.DEFAULT_DISPLAY, even when Nova was opened from the Thor bottom/companion screen.
• Differentiates stream display removal from companion display removal and unregisters the display listener.
• Adds safe display-role logs for field testing:
  • Nova: Android display role stream id=... target=...
  • Nova: Android display role companion id=... stream_id=...
  • Nova: Android display launch stream id=...

Field-test gate before merge

This PR should stay draft until real AYN Thor evidence confirms:

1. Enable Use Android external display.
2. Set Android stream display to Largest display or This device screen.
3. Launch Nova from the top screen, then launch a stream.
4. Confirm the game stays on the top/main screen.
5. Confirm the bottom screen shows Nova's touchpad/keyboard/menu controls.
6. Quit/disconnect cleanly.
7. Launch Nova from the bottom screen, then launch a stream.
8. Confirm the game still moves to the selected top/main stream display instead of leaving the top untouched.
9. Confirm the bottom screen shows Nova controls instead of a black placeholder.
10. Disconnect/relaunch once and confirm it does not hang at “preparing video, audio and controller input...”.
11. Open keyboard, full keyboard, menu, and zoom/pan once.
12. Attach or summarize a fresh Nova log if anything lands on the wrong screen.

Expected safe log shape:

Nova: Android display role stream id=0 target=largest
Nova: Android display launch stream id=0
Nova: Android display role companion id=4 stream_id=0

IDs may differ by firmware/device.

Test plan

Executed locally from an isolated worktree after initializing native submodules:

• RED guard: NovaExternalDisplayRoutingSourceGuardTest failed before the dedicated trampoline split because GameDisplayLaunchTrampolineActivity did not exist, ServerHelper still targeted ExternalDisplayControlActivity.EXTRA_LAUNCH_INTENT, ExternalDisplayControlActivity still bootstrapped Game, and Game.relaunchStream() still used plain app-context startActivity.
• ANDROID_HOME=/home/papi/Android/Sdk ANDROID_SDK_ROOT=/home/papi/Android/Sdk ./gradlew :app:testDebugUnitTest --tests com.papi.nova.utils.NovaExternalDisplayRoutingSourceGuardTest --tests com.papi.nova.utils.KotlinExternalDisplayUiMigrationTest --tests com.papi.nova.utils.AndroidStreamDisplayTargetTest --console=plain
• ANDROID_HOME=/home/papi/Android/Sdk ANDROID_SDK_ROOT=/home/papi/Android/Sdk ./gradlew :app:compileRootDebugKotlin :app:lintRootDebug :app:testDebugUnitTest :app:assembleDebug --console=plain
• After switching the trampoline from AppCompatActivity to plain Activity for the platform translucent theme: ANDROID_HOME=/home/papi/Android/Sdk ANDROID_SDK_ROOT=/home/papi/Android/Sdk ./gradlew :app:testDebugUnitTest --tests com.papi.nova.utils.NovaExternalDisplayRoutingSourceGuardTest --tests com.papi.nova.utils.KotlinExternalDisplayUiMigrationTest --tests com.papi.nova.utils.AndroidStreamDisplayTargetTest :app:compileRootDebugKotlin :app:lintRootDebug :app:assembleDebug --console=plain
• git diff --check
• Static added-line scan for secrets/shell/eval/pickle/SQL patterns: no findings.
• Lint XML changed-line scan: no findings on changed lines.

Debug APKs were produced locally for root/non-root debug flavors and arm64-v8a/armeabi-v7a/x86_64 ABIs.

Field-test APK

Prerelease asset:
https://github.com/papi-ux/nova/releases/tag/pr117-thor-dual-screen-debug

Current arm64-v8a debug APK SHA256:
05bbb02598c5a4c97eb4e8c6d4156f243ac9e448afda2e18370393151116e53b

Notes

• This is Lane A only: functional dual-display routing and lifecycle cleanup.
• It intentionally does not include the later companion dashboard / NovaHUD polish lane.
• No Polaris host/protocol changes are included.
• Logging is limited to display role/id/target/stream_id; no host credentials, certs, tokens, IPs, URLs, or computer names are logged by the new role lines.
• If audio still routes to the bottom/control display after this build, treat that as a separate Android audio-output routing follow-up with a fresh log and exact device-output behavior.

[papi-ux]

Thor field-test APK for this PR

I published a debug-signed arm64 field-test APK for PR #117 here:

• Release: https://github.com/papi-ux/nova/releases/tag/pr117-thor-dual-screen-debug
• APK: https://github.com/papi-ux/nova/releases/download/pr117-thor-dual-screen-debug/Nova-PR117-Thor-arm64-v8a-debug.apk
• SHA-256: 7143ed538ad0f6ee4822e2bab014a0174d2fd72bea96001a821835b7fe098253

This APK is debug-signed for testing only:

C=US, O=Android, CN=Android Debug

If Android reports a signature mismatch, uninstall the existing release build first, then install this APK:

adb uninstall com.papi.nova
adb install Nova-PR117-Thor-arm64-v8a-debug.apk

Thor test checklist

1. Install the APK on the Thor.
2. Open Nova and connect/pair normally.
3. Enable Use Android external display.
4. Set Android stream display to Largest display or This device screen.
5. Launch a stream.
6. Confirm the game stays on the top/main screen.
7. Confirm the bottom screen shows Nova's touchpad/keyboard/menu controls.
8. Exercise once:
   • touchpad movement/click
   • Android soft keyboard
   • full keyboard
   • game menu / quick shortcuts
   • zoom/pan toggle
9. Quit the stream.
10. Confirm the bottom controls close cleanly, no stuck notification remains, and relaunch works.

Logs to capture if anything lands wrong

Please attach/summarize fresh Nova logs containing these lines:

Nova: Android display role stream id=... target=...
Nova: Android display role companion id=... stream_id=...

Expected Thor-ish shape for Largest display:

Nova: Android display role stream id=0 target=largest
Nova: Android display role companion id=4 stream_id=0

Display IDs may differ by firmware/device.

This PR should remain draft until real Thor hardware confirms the routing behavior.