FIX: root-own the Salt default tree so a SOC file-write cannot reach root code

/opt/so/saltstack/default holds the source for every root-executed script --
/usr/sbin, the reactors, _runners/_modules/_beacons, the master engines and
salt-relay.sh -- plus every state the root master renders. SOC mounts
/opt/so/saltstack rw as uid 939, so root-owning /usr/sbin alone was not
enough: the next highstate would copy attacker-controlled bytes out of the
tree into the root-owned destination and run them.

SOC never writes under default/, it only reads it. Every SOC write targets
local/, which stays socore-owned, as does /opt/so/state. No mode is enforced
on default/ -- SOC reads that tree, and 750/640 would break its config load.

Also stops copy_new_files(), so-saltstack-update and setup from chowning the
tree back to socore, and replaces preserve: True in soup_scripts.sls, which
carried uid/gid in from the /tmp staging tree and would have undone the
ownership before the first post-soup highstate.

salt/manager/init.sls

@@ -190,11 +190,15 @@ so_fleetagent_monitor:
   - month: '*'
   - dayweek: '*'
 
-socore_own_saltstack_default:
+# This tree is the source of every root-executed script (/usr/sbin, reactors, _runners,
+# engines, salt-relay.sh). SOC mounts /opt/so/saltstack rw as uid 939 but only writes
+# under local/. Do not add dir_mode/file_mode here -- SOC reads default/ and 750/640
+# would break its config load.
+root_own_saltstack_default:
   file.directory:
     - name: /opt/so/saltstack/default
-    - user: socore
-    - group: socore
+    - user: root
+    - group: root
     - recurse:
       - user
       - group

salt/manager/tools/sbin/so-saltstack-update

@@ -124,8 +124,8 @@ copy_new_files() {
   
   rsync -a salt $default_salt_dir/
   rsync -a pillar $default_salt_dir/
-  chown -R socore:socore $default_salt_dir/salt
-  chown -R socore:socore $default_salt_dir/pillar
+  chown -R root:root $default_salt_dir/salt
+  chown -R root:root $default_salt_dir/pillar
   chmod 755 $default_salt_dir/pillar/firewall/addfirewall.sh
 
   rm -rf /tmp/sogh