chore(ui): improve hash parsing + test - WF-72

It's possible to use `URLSearchParams` instead of complex Regex. As it's
a very testable part of the code, it was a good opportunity to introduce
Vitest and cover it.

This improvement made me realise that a bug was present, and we didn't
serialize the params when converting back the object to hash (`.key =
length` was not called).

alfred/ci.py

@@ -18,6 +18,7 @@ def ci(front, back, e2e, docs):
     if front or no_flags:
         alfred.invoke_command("npm.lint")
         alfred.invoke_command("npm.build")
+        alfred.invoke_command("npm.ui.test")
     if back or no_flags:
         alfred.invoke_command("ci.mypy")
         alfred.invoke_command("ci.ruff")

alfred/npm.py

@@ -26,6 +26,10 @@ def npm_build_custom_components():
 def npm_docs_test():
     alfred.run("npm run docs:test")
 
+@alfred.command("npm.ui.test", help="test against writer-ui")
+def npm_ui_test():
+    alfred.run("npm run -w writer-ui test")
+
 @alfred.command("npm.storybook", help="build storybook for continuous integration")
 def npm_storybook():
     os.chdir("src/ui")