docs: Implement FAQ page, default values in Cue + fix sidebar and titles

Move faq pages from guide to specific FAQ page, shown as per tailscale format.
Custom in-house logic implemented because Docusaurus doesn't manage it

Signed-off-by: guillaume <guillaume.derouville@gmail.com>

docs/faq/1229-empty-buildkit-cache.md

@@ -1,9 +1,9 @@
 ---
-slug: /1227/empty-buildkit-cache
+slug: /1229/empty-buildkit-cache
 displayed_sidebar: europa
 ---
 
-# How to empty BuildKit's cache ?
+# Empty BuildKit's cache
 
 There are two ways of emptying the BuildKit cache:
 

docs/faq/1230-better-logs.md

@@ -1,9 +1,9 @@
 ---
-slug: /1228/better-logs
+slug: /1230/better-logs
 displayed_sidebar: europa
 ---
 
-# How can I have better logs ?
+# Log formats
 
 Dagger exposes 2 logging format options:
 

docs/faq/1231-always-execute.md

@@ -1,9 +1,9 @@
 ---
-slug: /1229/always-execute
+slug: /1231/always-execute
 displayed_sidebar: europa
 ---
 
-# How to make sure an action is always being executed ?
+# Always executing an action
 
 Dagger implemented a way to tell Buildkit not to rely on cache for a specific action.
 

docs/faq/1232-chain-actions.md

@@ -1,9 +1,9 @@
 ---
-slug: /1230/chain-actions
+slug: /1232/chain-actions
 displayed_sidebar: europa
 ---
 
-# How can I chain actions together ?
+# Chaining actions
 
 Dependencies are materialized at runtime, when your Cue files are parsed and the corresponding DAG gets generated:
 

docs/faq/index.md

@@ -0,0 +1,33 @@
+---
+slug: /faq
+displayed_sidebar: europa
+---
+
+# FAQ
+
+```mdx-code-block
+import DocCardList from '@theme/DocCardList';
+import {useDocsVersion} from '@docusaurus/theme-common';
+
+export const FaqItems = () => {
+    {/* access root category object from Docusaurus */}
+    const docsVersion = useDocsVersion();
+    {/* customProps object retrieved from sidebar.js */}
+    const faqItem = docsVersion.docsSidebars.europa.filter(item => item.label === 'FAQ');
+    {/* Return custom FAQ Items array */}
+    const customPropsItem = faqItem[0].customProps.items.map(customPropsItem => {
+        const result = Object.values(docsVersion.docs).filter(item => item.id === customPropsItem.docId)[0]
+        if(result)
+            return {
+                type: "link",
+                label: result.title,
+                description: result.description,
+                href: customPropsItem.href,
+                docId: customPropsItem.docId
+            }
+    })
+    return <DocCardList items={customPropsItem}/>
+}
+
+<FaqItems />
+```

website/sidebars.js

@@ -57,6 +57,19 @@ module.exports = {
       	"guides/migrate-from-dagger-0.1",
       ],
     },
+    {
+      type: "doc",
+      label: "FAQ",
+      id: "faq/index",
+      customProps: {
+        "items": [
+          { docId: "faq/empty-buildkit-cache", href: "1229/empty-buildkit-cache" },
+          { docId: "faq/better-logs", href: "1230/better-logs" },
+          { docId: "faq/always-execute", href: "1231/always-execute" },
+          { docId: "faq/chain-actions", href: "1232/chain-actions" },
+        ]
+      }
+    },
     {
       type: "category",
       label: "References",