fix(android): repair AOSP build entry points and Telecom defaults

[lalalune]

Android Telecom resolves its default dialer components from product resources. Point those resources at Eliza’s in-call service and activity so the image uses the native call UI without a shell override.

Also pass the validated AOSP output directory to Soong relative to the source root. Android 17 Siso requires a relative configuration repository path: the previous absolute OUT_DIR made bootstrap fail to load main.star even though it existed. Canonical directory ownership, identity and temporary-directory checks remain in place; external and symlinked output directories keep their targets.

The privileged APK rebuild entry now checks the current packages/app checkout instead of retired packages/app-core. A real child-process regression checks working directory, branded build flags and nonzero exit propagation. Removed the unused duplicate launcher/splash generator; those assets remain owned by the application build. Remove the unused branding keys from the contributor guide and correct the documented Android package ID.

Validation: full OS repository bun run verify passes, including 58 AOSP build-contract tests. The pinned Siso binary reproduces the absolute-path failure and passes dry runs with relative internal and external configuration paths. The proposed Telecom resource overlay was compiled, installed and exercised on the dedicated Android 17 Cuttlefish instance; ring, answer, mute and end-call work without a command-line component override.

The current application release separately passes 142 native device tests across 20 modules and production startup with existing data preserved. All required CI jobs pass, including both retained-FD virtual-disk restore jobs. Two full isolated Android 17 image attempts passed the repaired bootstrap boundary but were terminated by systemd-oomd during graph generation; the latest used actual two-core affinity and reached 6.5 GiB resident plus 24 GiB swap after 72 minutes. No complete image was produced. Image compilation and fresh-image boot remain uncertified, so this PR remains draft.