Remove duplicate guides from kit (#385)

This removes the duplicate install guide, how to guides, branching examples and passing data from page to page examples, and the documentation homepage from kit.

These guides are all now hosted separately in on the [NHS.UK prototype kit](https://prototype-kit.service-manual.nhs.uk) website and maintained within a separate repository: [nhsuk.service-manual.prototype-kit.docs](http://github.com/nhsuk/nhsuk.service-manual.prototype-kit.docs).

This is intended to allow us to update the guidance more frequently (outside of the prototype kit release cycle). It also means that uses of the kit will always access the most up-to-date versions of the guidance, even if their prototype is a few versions old. 

The one acknowledged downside is that it means you now need to be online to view the guidance, vs having a local copy.

The one bit I’ve not removed is the collection of example page templates. These are also duplicated on the prototype kit website at https://prototype-kit.service-manual.nhs.uk/page-templates - however they might be more useful to have locally, as it’ll be easier to copy-and-paste them.  I've created a separate issue to consider what the best thing to do with the templates is: [#60](nhsuk/nhsuk.service-manual.prototype-kit.docs#60).

CHANGELOG.md

@@ -1,5 +1,9 @@
 # NHS.UK prototype kit Changelog
 
+## Unreleased
+
+- Remove guidance and tutorials - these can now be found online on the [NHS Prototype Kit website](https://prototype-kit.service-manual.nhs.uk) - ([PR 385](https://github.com/nhsuk/nhsuk-prototype-kit/pull/385))
+
 ## 5.0.0 - 15 October 2024
 
 :new: **New features**

app.js

@@ -213,11 +213,6 @@ if (useDocumentation || onlyDocumentation === 'true') {
   });
 }
 
-// Clear all data in session if you open /examples/passing-data/clear-data
-app.post('/examples/passing-data/clear-data', (req, res) => {
-  req.session.data = {};
-  res.render('examples/passing-data/clear-data-success');
-});
 
 app.use('/prototype-admin', prototypeAdminRoutes);
 

app/views/index.html

@@ -4,9 +4,9 @@
 
 <!-- Extends the layout from /views/layout.html -->
 {% extends 'layout.html' %}
-<!-- 
+<!--
   In /views/layout.html you can:
-    - change the header and footer 
+    - change the header and footer
     - add custom CSS and JavaScript
 -->
 
@@ -49,13 +49,13 @@ <h2>
       <p>
         Use this page as the index for your project.
       </p>
-      
+
       <p>
         You'll find the code for this page at <strong>/app/views/index.html</strong>.
       </p>
 
       <p>
-        There is also an <a href="/page-example">example page</a>, which contains a selection of NHS.UK frontend styles and components.
+        There is also an <a href="/page-example">example page</a>, which contains a selection of NHS.UK frontend styles and components and some <a href="/docs/page-templates">page templates</a>.
       </p>
 
       <hr>
@@ -68,10 +68,7 @@ <h2>
 
       <ul>
         <li>
-          <a href="/docs/how-tos">how to guides</a>
-        </li>
-        <li>
-          <a href="/docs/page-templates">page templates</a>
+          <a href="https://prototype-kit.service-manual.nhs.uk/how-tos">how to guides</a>
         </li>
         <li>
           code snippets for styles and components from the <a href="https://service-manual.nhs.uk/design-system">NHS digital service manual</a>

docs/documentation_routes.js

@@ -4,56 +4,4 @@ const packageJson = require('../package.json');
 
 const router = express.Router();
 
-// Documentation router
-router.get('/', (req, res) => {
-  res.render('index');
-});
-
-// Install guide branching
-router.post('/install', (req, res) => {
-  const { install } = req.session.data;
-
-  if (install === 'Simple') {
-    res.redirect('/docs/install/simple');
-  }
-  if (install === 'Developer') {
-    res.redirect('/docs/install/advanced');
-  } else {
-    res.redirect('/docs/install/download-zip');
-  }
-});
-
-// Install - Mac or Windows branching
-router.post('/install/mac', (req, res) => {
-  const { machine } = req.session.data;
-
-  if (machine === 'Mac') {
-    res.redirect('/docs/install/mac/terminal');
-  } else {
-    res.redirect('/docs/install/windows/terminal');
-  }
-});
-
-router.get('/download', (req, res) => {
-  const { version } = packageJson;
-  res.redirect(
-    `https://github.com/nhsuk/nhsuk-prototype-kit/archive/refs/tags/v${version}.zip`,
-  );
-});
-
-// Branching example
-router.post('/examples/branching/answer', (req, res) => {
-  // Make a variable and give it the value from 'know-nhs-number'
-  const nhsNumber = req.session.data['know-nhs-number'];
-
-  // Check whether the variable matches a condition
-  if (nhsNumber === 'Yes') {
-    // Send user to next page
-    res.redirect('/docs/examples/branching/answer-yes');
-  } else {
-    // Send user to ineligible page
-    res.redirect('/docs/examples/branching/answer-no');
-  }
-});
-
 module.exports = router;