- Moved build scripts to scripts directory:
  - build_client.sh -> scripts/build_client.sh
  - build_server.sh -> scripts/build_server.sh
- Added new run script: scripts/run_client.sh

Merge branch 'executionManager' of https://gitlab.eduxiji.net/T202410002993466/db2024-rmdb into executionManager

Merge branch 'executionManager' of https://gitlab.eduxiji.net/T202410002993466/db2024-rmdb into executionManager

- Added maintain_parent() and release_node_handle() where necessary
- Modified functions related to IxIndexHandle::coalesce_or_redistribute