[docs] Add references to the Idris2 tutorial

Serves as a much more thorough introduction than the crash course, and
we should definitely be pointing people more in that direction.

Author: CodingCellist

src/content/pages/docs/index.rst

@@ -14,6 +14,11 @@ This includes:
 * `Changes required <https://idris2.readthedocs.io/en/latest/typedd/typedd.html>`_
   to the code in `Type Driven Development with Idris <https://www.manning.com/books/type-driven-development-with-idris>`_.
 
+The
+`community-maintained Idris2 tutorial <https://idris-community.github.io/idris2-tutorial/>`_
+(originally written by Stefan Höck for undergraduate university teaching) is an
+excellent entry-point.
+
 There is API documentation for the following packages:
 
 * `prelude <https://www.idris-lang.org/Idris2/prelude>`__

src/content/pages/example.rst

@@ -1,7 +1,7 @@
 Example
 =======
 
-:date: 2020-04-01 11:00
+:date: 2025-10-16 17:30
 
 Idris is a purely functional programming language, with first class types
 - meaning that types are first class language constructs, and can be computed,
@@ -91,7 +91,12 @@ lengths of the inputs:
     app Nil       ys = ys
     app (x :: xs) ys = x :: app xs ys
 
-For more details, see `the tutorial <https://idris2.readthedocs.io/en/latest/tutorial/index.html>`_.
+For more details and quickly getting up to speed, there is
+`the "Crash Course in Idris2" <https://idris2.readthedocs.io/en/latest/tutorial/index.html>`_.
+
+For a more beginner-friendly tutorial, please see
+`the community-maintained Idris2 tutorial <https://idris-community.github.io/idris2-tutorial/>`_,
+originally written by Stefan Höck for undergraduate university teaching.
 
 Talks
 -----