feat(packages): add free5gc/connectivity OKAs and fix environment limitations

- Add connectivity_ns package (VL-only NS, no NFs)
- Add free5gc-core KSU OKA for declarative Flux deployment
- Add free5gc-upf KSU OKA with fullnameOverride workaround for K8s
  volume name >63-char limit imposed by OSM release name format
- Add free5gc-core-app and free5gc-upf-app OKAs for declarative app mode
- Add params files for free5gc-core and free5gc-upf (KSU and app modes)
- Fix free5gc-upf_ns params: per-subchart fullnameOverride to avoid
  volume name length limit; switch mongodb to bitnamilegacy/mongodb
  (bitnami removed versioned tags from Docker Hub); pin free5gc-smf
  image to v4.2.2 (v4.1.0 missing /sbin/tini required by chart entrypoint)
- Fix free5gc-core_ns params: set deployUpf:false and configure mongodb
  with dynamic provisioning via local-path StorageClass
- Update oai-5g-core-app OKA: switch oai-amf and oai-lmf to
  frnetsoft:develop images to enable LMF positioning support
- Remove tracked macOS .DS_Store files

Known environment limitations:
- Mobsim LMF geolocation requires kubectl port-forward from the mgmt VM;
  direct NodePort access bypasses the callback path used by frnetsoft AMF
- frnetsoft/mobsim and trf-gen-cn5g only publish :latest; digest pinning
  not supported without chart template changes
- free5gc-upf and free5gc-core cannot coexist in the same K8s namespace;
  must be deployed sequentially