Add OpenObservation setup to CI pipeline

- Create openobservation_setup.sh script to clone OpenObservation repository
- Update darwin_setup_build.sh to include OpenObservation setup
- Fix CI failures caused by missing local OpenObservation dependency

Author: Kyle-Ye

Scripts/CI/darwin_setup_build.sh

@@ -11,4 +11,5 @@ cd $REPO_ROOT
 Scripts/CI/opencoregraphics_setup.sh
 Scripts/CI/openattributegraph_setup.sh
 Scripts/CI/openrenderbox_setup.sh
+Scripts/CI/openobservation_setup.sh
 Scripts/CI/framework_setup.sh

Scripts/CI/openobservation_setup.sh

@@ -0,0 +1,19 @@
+#!/bin/bash
+
+# A `realpath` alternative using the default C implementation.
+filepath() {
+    [[ $1 = /* ]] && echo "$1" || echo "$PWD/${1#./}"
+}
+
+REPO_ROOT="$(dirname $(dirname $(dirname $(filepath $0))))"
+cd $REPO_ROOT/..
+
+if [ ! -d OpenObservation ]; then
+  gh repo clone OpenSwiftUIProject/OpenObservation
+else
+  echo "OpenObservation already exists, updating it."
+  cd OpenObservation
+  git fetch --all --quiet
+  git stash --quiet || true
+  git reset --hard --quiet origin/main
+fi