Render ThematicBreak wider

app/Polysemy/Commonmark/AST.hs

@@ -174,7 +174,8 @@ instance PrintColor Block where
       printColor i
     printBlockOne prefix ThematicBreak = do
       putTextO prefix
-      putTextLnO "---"
+      -- TODO: this should depend on terminal width
+      putTextLnO . fromString $ replicate (80 - T.length prefix) '─'
     printBlockOne prefix (BlockQuote b) = printBlockP (prefix <> "> ") b
     printBlockOne prefix (CodeBlock lang content) = do
       putTextLnO $ prefix <> "```" <> lang