test: add unit test for Typst path API

Author: mcanouil

tests/docs/smoke-all/2025/12/05/typst-path-api.lua

@@ -0,0 +1,7 @@
+function typst_path()
+  return quarto.paths.typst()
+end
+
+return {
+  ["typst"] = typst_path
+}

tests/docs/smoke-all/2025/12/05/typst-path-api.qmd

@@ -0,0 +1,12 @@
+---
+format: html
+shortcodes:
+  - typst-path-api.lua
+_quarto:
+  tests:
+    html:
+      ensureFileRegexMatches:
+        - ["<p>The Typst path is .+.</p>"]
+---
+
+The Typst path is "{{< typst >}}".