Take ui-trace to the adb beside it

ui-trace found adb on PATH, and this machine's ambient PATH puts the SDK's
own platform-tools ahead of ~/.local/bin -- so unless a project's
android-env.sh had been sourced into that same shell, ui-trace drove the
device through the unwrapped adb and failed with "more than one device" as
soon as a second emulator was up. The wrapper installed beside it is the one
that knows which emulator this checkout means, so it is now the first
candidate rather than a coincidence of PATH order.

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

.gitignore

@@ -0,0 +1,5 @@
+# Built by share/ui-trace/build.sh when the source is newer, and pushed to
+# the device by ui-trace. Rebuilt on demand, so it is not worth committing --
+# and a jar committed here would go stale against UiTrace.java without saying
+# so.
+share/ui-trace/uitrace.jar