Remove definitions.typst partial.

Remove unnecessary definition of `endnote`.
Incorporate the one remaining definition into `default.typst`.

data/templates/default.typst

@@ -1,4 +1,4 @@
-$definitions.typst()$
+#let horizontalrule = line(start: (25%,0%), end: (75%,0%))
 
 #show terms: it => {
   it.children

data/templates/definitions.typst

@@ -1,8 +0,0 @@
-// Some definitions presupposed by pandoc's typst output.
-#let horizontalrule = [
-  #line(start: (25%,0%), end: (75%,0%))
-]
-
-#let endnote(num, contents) = [
-  #stack(dir: ltr, spacing: 3pt, super[#num], contents)
-]

pandoc.cabal

@@ -102,7 +102,6 @@ data-files:
                  data/templates/affiliations.jats
                  data/templates/default.markua
                  data/templates/default.typst
-                 data/templates/definitions.typst
                  data/templates/template.typst
                  data/templates/common.latex
                  data/templates/hypersetup.latex

test/writer.typst

@@ -1,11 +1,5 @@
-// Some definitions presupposed by pandoc's typst output.
-#let horizontalrule = [
-  #line(start: (25%,0%), end: (75%,0%))
-]
+#let horizontalrule = line(start: (25%,0%), end: (75%,0%))
 
-#let endnote(num, contents) = [
-  #stack(dir: ltr, spacing: 3pt, super[#num], contents)
-]
 #show terms: it => {
   it.children
     .map(child => [