The shared upstream pin, license, and C API headers lived inside the
mobile terminal module, so the web adapter's build script, ABI
regression test, and docs reached across into apps/mobile. The
canonical vendor now lives at native/libghostty-vt/ beside the other
top-level native code, and both platforms reference it there:

- Android's CMake include path and the Android build script follow
- the web WASM build script and the ABI test read the root pin
- docs and third-party notices point at the new location

Platform build outputs stay with their apps (Android jniLibs and the
iOS xcframework in the mobile module, the wasm artifacts in the web
adapter). The web WASM build was re-run from the relocated pin to
verify the script end to end; the artifact is byte-identical.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>