Integrate zosstorage build path and runtime orchestration

Summary:

* add openssh-client to the builder image and mount host SSH keys into the dev container when available

* switch RFS to git builds, register the zosstorage source, and document the extra Rust component

* wire zosstorage into the build: add build_zosstorage(), ship the binary in the initramfs, and extend component validation

* refresh kernel configuration to 6.12.49 while dropping Xen guest selections and enabling counted-by support

* tighten runtime configs: use cached mycelium key path, add zosstorage zinit unit, bootstrap ovsdb-server, and enable openvswitch module

* adjust the network health check ping invocation and fix the RFS pack-tree --debug flag order

* update NOTES changelog, README component list, and introduce a runit helper for qemu/cloud-hypervisor testing

* add ovsdb init script wiring under config/zinit/init and ensure zosstorage is available before mycelium

config/sources.conf

@@ -4,7 +4,8 @@
 # Git repositories to clone and build
 git zinit https://github.com/threefoldtech/zinit master build_zinit
 git mycelium https://github.com/threefoldtech/mycelium v0.6.1 build_mycelium
-
+git zosstorage git@git.ourworld.tf:delandtj/zosstorage main build_zosstorage
+git rfs https://github.com/threefoldtech/rfs development build_rfs
 # Pre-built releases to download
-release rfs https://github.com/threefoldtech/rfs/releases/download/v2.0.6/rfs v2.0.6 install_rfs
+# release rfs https://github.com/threefoldtech/rfs/releases/download/v2.0.6/rfs v2.0.6 install_rfs
 release corex https://github.com/threefoldtech/corex/releases/download/2.1.4/corex-2.1.4-amd64-linux-static 2.1.4 install_corex rename=corex