Add con files

pkg/arvo/neo/cod/std/src/con/node-counter-diff.hoon

@@ -0,0 +1,9 @@
+/@  node
+/@  counter-diff
+/-  manx-utils
+:-  [%node %$ %counter-diff]
+|=  =node
+^-  counter-diff
+=/  mu     ~(. manx-utils node)
+=/  head   (?(%inc) (got:mu %head))
+[head ~]

pkg/arvo/neo/cod/std/src/con/number-htmx.hoon

@@ -0,0 +1,21 @@
+/@  number
+/-  feather-icons
+:-  [%number %$ %htmx]
+|=  =number
+|=  =bowl:neo
+^-  manx
+;div.fc.ac.br2
+  ;h2:  {<number>}
+  ;form
+  =hx-post       "/neo/hawk{(en-tape:pith:neo here.bowl)}?stud=counter-diff"
+  =hx-on-submit  "this.reset()"
+  =hx-target     "find .loading"
+  =head          "inc"
+    ;button.bd3.p2.hover
+      ;span.loaded:  Increment
+      ;span.loading
+        ;+  loading.feather-icons
+      ==
+    ==
+  ==
+==