[pixels-core, script] Improve deployment path compatibility

[AntiO2]

Problem

Deployment scripts assume a shared installation path and a preconfigured Java environment. This breaks heterogeneous clusters where nodes use different PIXELS_HOME or JDK locations. In particular, daemon shutdown can fail because jps is not on PATH, and install.sh references a non-existent C++ properties template. Buffer object-storage folders without a trailing slash also form invalid object keys.

Proposed fix

• Normalize the retina buffer storage folder with a trailing slash.
• Resolve Java from a valid JAVA_HOME, PATH, or common node-local JDK locations; export its bin directory so jps is available.
• Run remote worker/retina lifecycle commands against the target node's PIXELS_HOME and rewrite copied absolute paths during cluster sync.
• Copy cpp/etc/pixels-cpp.properties from the installer.

Validation

• bash -n install.sh scripts/bin/run-class.sh scripts/sbin/rsync-cluster.sh scripts/sbin/start-retina.sh scripts/sbin/start-workers.sh scripts/sbin/stop-retina.sh scripts/sbin/stop-workers.sh
• mvn -pl pixels-core -DskipTests package