Doc: Update use cases

readme/apps/sync/_category_.yml

@@ -1,4 +1,4 @@
-position: 1
+position: 2
 label: 'Synchronisation'
 collapsible: true
 collapsed: true

readme/apps/use_cases/_category_.yml

@@ -0,0 +1,4 @@
+position: 1
+label: 'Use cases'
+collapsible: true
+collapsed: true

readme/apps/use_cases/personal_organisation.md

@@ -13,13 +13,13 @@ If you're preparing a trip or holidays, Joplin will help you keep track of all i
 - List potential destinations, attractions, and activities. Note down the best time to visit, local customs, and must-try local cuisines. You can also create an itinerary for each day of your trip.
 - Prepare your packing list. For better organization, you can divide the list between different categories like clothes, toiletries, gadgets, and travel documents .
 
-<img src="https://raw.githubusercontent.com/laurent22/joplin/dev/Assets/WebsiteAssets/images/use_cases/personal_organisation/prepare.png" style="max-width: 500px;/>
+<img src="https://raw.githubusercontent.com/laurent22/joplin/dev/Assets/WebsiteAssets/images/use_cases/personal_organisation/prepare.png" style="max-width: 500px;" />
 
 ## 2\. Make lists of things to buy or do
 
 Make lists for daily tasks like shopping or long-term projects like personal goals. Use checklists, bullet lists and numbered lists to organise your tasks.
 
-<img src="https://raw.githubusercontent.com/laurent22/joplin/dev/Assets/WebsiteAssets/images/use_cases/personal_organisation/make_list.png" style="max-width: 500px;/>
+<img src="https://raw.githubusercontent.com/laurent22/joplin/dev/Assets/WebsiteAssets/images/use_cases/personal_organisation/make_list.png" style="max-width: 500px;" />
 
 ## 3\. Store your important documents and access them anytime
 
@@ -31,10 +31,10 @@ You can store important documents, attach payment confirmations and receipts. Yo
 
 You can save interesting articles, web pages, blog posts or recipes and save them to Joplin thanks to Joplin web clipper extension.
 
-<img src="https://raw.githubusercontent.com/laurent22/joplin/dev/Assets/WebsiteAssets/images/use_cases/personal_organisation/web_clipper.png" style="max-width: 500px;/>
+<img src="https://raw.githubusercontent.com/laurent22/joplin/dev/Assets/WebsiteAssets/images/use_cases/personal_organisation/web_clipper.png" style="max-width: 500px;" />
 
 ## 5\. Sharing and gather informations with your travelling companions
 
 Efficiently share travel plans, itineraries, and important updates with your travel partners using Joplin even if they don't. Easily gather and consolidate input and suggestions from everyone involved to ensure a well-coordinated and enjoyable trip.
 
-<img src="https://raw.githubusercontent.com/laurent22/joplin/dev/Assets/WebsiteAssets/images/use_cases/personal_organisation/publish.png" style="max-width: 500px;/>
+<img src="https://raw.githubusercontent.com/laurent22/joplin/dev/Assets/WebsiteAssets/images/use_cases/personal_organisation/publish.png" style="max-width: 500px;" />