LuaSnip: Add markdown snippet for inserting code snippets

lua/custom/snippets/markdown.lua

@@ -1,10 +1,15 @@
 require("luasnip.session.snippet_collection").clear_snippets "markdown"
+
 local ls = require "luasnip"
+
 local s = ls.snippet
 local t = ls.text_node
+local c = ls.choice_node
 local i = ls.insert_node
 local f = ls.function_node
 
+local fmt = require("luasnip.extras.fmt").fmt
+
 ls.add_snippets(
   "markdown",
   {
@@ -19,4 +24,18 @@ ls.add_snippets(
       end),
       t(")"), i(0),
     }),
-  })
+    s({ trig = "ics", dscr = "Insert code snippet" },
+      fmt(
+        [[
+          ```{}
+          {}
+          ```
+        ]],
+        {
+          c(1, { t "python", t "bash", t "swift", t "c" }),
+          i(2),
+        }
+      )
+    )
+  }
+)