post: remove %dm reference

pkg/arvo/app/chat-cli.hoon

@@ -1200,8 +1200,6 @@
         ::
           %group
         txt+"[reference to msg in {~(phat tr group.reference.content)}]"
-          %dm
-        txt+"[reference to DM with {(scow %p ship.reference.content)}]"
       ==
     ::
         %mention

pkg/arvo/app/graph-store.hoon

@@ -763,10 +763,13 @@
     :+  now.bowl  %add-nodes
     :-  [ship term]
     %-  ~(gas by *(map index:store node:store))
-    %+  turn  (tap:orm u.children)
+    %+  murn  (tap:orm u.children)
     |=  [=atom =node:store]
-    ^-  [index:store node:store]
-    :-  index.post.node
+    ^-  (unit [index:store node:store])
+    ?.  ?=(%& -.post.node)  ~
+    =*  p  p.post.node
+    :-  ~
+    :-  index.p
     node(children [%empty ~])
   ::
       [%x ?(%newest %oldest) @ @ @ *]

pkg/arvo/lib/graph-store.hoon

@@ -99,18 +99,10 @@
     |^
     %+  frond  -.ref
     ?-  -.ref
-      %dm     (dm +.ref)
       %graph  (graph +.ref)
       %group  (group +.ref)
     ==
     ::
-    ++  dm
-      |=  [s=^ship idx=^index]
-      %-  pairs
-      :~  ship+(ship s)
-          index+(index idx)
-      ==
-    ::
     ++  graph
       |=  [grp=res gra=res idx=^index]
       %-  pairs
@@ -385,15 +377,8 @@
       %-  of
       :~  graph+graph
           group+dejs-path:res
-          dm+dm
       ==
       ::
-      ++  dm
-        %-  ot
-        :~  ship+(su ;~(pfix sig fed:ag))
-            index+index
-        ==
-      ::
       ++  graph
         %-  ot
         :~  group+dejs-path:res

pkg/arvo/sur/post.hoon

@@ -29,7 +29,6 @@
 +$  reference
   $%  [%graph group=resource =uid]
       [%group group=resource]
-      [%dm =ship =index]
   ==
 ::
 +$  content