docs: add routing page (#9550)

- Add a new homepage to `book` project for the routing page
- Move all main doc pages to be under `/v2/learn` (and added redirects + fixed links across docs)
- Other: add admin components to resources dropdown + fixes to search on mobile.

Closes DX-955

Preview: https://docs-v2-git-docs-router-page-medusajs.vercel.app/v2

www/apps/resources/app/recipes/subscriptions/examples/standard/page.mdx

@@ -168,9 +168,9 @@ module.exports = defineConfig({
 
 ### Further Read
 
-- [How to Create a Module](!docs!/basics/modules)
-- [How to Create a Data Model](!docs!/basics/modules#1-create-data-model)
-- [Learn more about the service factory](!docs!/advanced-development/modules/service-factory).
+- [How to Create a Module](!docs!/learn/basics/modules)
+- [How to Create a Data Model](!docs!/learn/basics/modules#1-create-data-model)
+- [Learn more about the service factory](!docs!/learn/advanced-development/modules/service-factory).
 
 ---
 
@@ -243,7 +243,7 @@ This defines a list link to the `Order` data model since a subscription has mult
 
 ### Further Reads
 
-- [How to Define a Link](!docs!/advanced-development/module-links)
+- [How to Define a Link](!docs!/learn/advanced-development/module-links)
 
 ---
 
@@ -640,9 +640,9 @@ The workflow returns the created subscription and order.
 
 ### Further Reads
 
-- [How to Create a Workflow](!docs!/basics/workflows)
-- [Learn more about the compensation function](!docs!/advanced-development/workflows/compensation-function)
-- [How to use the Remote Link](!docs!/advanced-development/module-links/remote-link)
+- [How to Create a Workflow](!docs!/learn/basics/workflows)
+- [Learn more about the compensation function](!docs!/learn/advanced-development/workflows/compensation-function)
+- [How to use the Remote Link](!docs!/learn/advanced-development/module-links/remote-link)
 
 ---
 
@@ -954,7 +954,7 @@ npm run dev
 
 ### Further Reads
 
-- [How to Create an API Route](!docs!/basics/api-routes)
+- [How to Create an API Route](!docs!/learn/basics/api-routes)
 
 ---
 
@@ -1431,7 +1431,7 @@ To view a subscription’s details, click on its ID, which opens the subscriptio
 
 ### Further Reads
 
-- [How to Create UI Routes](!docs!/advanced-development/admin/ui-routes)
+- [How to Create UI Routes](!docs!/learn/advanced-development/admin/ui-routes)
 
 ---
 
@@ -1983,7 +1983,7 @@ This loops over the returned subscriptions and executes the `createSubscriptionO
 
 ### Further Reads
 
-- [How to Create a Scheduled Job](!docs!/basics/scheeduled-jobs)
+- [How to Create a Scheduled Job](!docs!/learn/basics/scheeduled-jobs)
 
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