Add Inky-based, WIDM-styled email templates (#212)

Adds twig/inky-extra and twig/cssinliner-extra to build the password
reset and email confirmation emails from a shared responsive layout,
styled after the quiz's green/black look, with Dutch copy in the
show's dramatic tone.

composer.json

@@ -49,7 +49,9 @@
         "symfonycasts/sass-bundle": "^0.10",
         "symfonycasts/verify-email-bundle": "^1.18.0",
         "thecodingmachine/safe": "^3.4.0",
+        "twig/cssinliner-extra": "^3.26.0",
         "twig/extra-bundle": "^3.24.0",
+        "twig/inky-extra": "^3.26.0",
         "twig/intl-extra": "^3.24.0",
         "twig/markdown-extra": "^3.24.0",
         "twig/twig": "^3.27.1"