docs: updates to use DML and other changes (#7834)

- Change existing data model guides and add new ones for DML
- Change module's docs around service factory + remove guides that are now necessary
- Hide/remove all mentions of module relationships, or label them as coming soon.
- Change all data model creation snippets to use DML
- use `property` instead of `field` when referring to a data model's properties.
- Fix all snippets in commerce module guides to use new method suffix (no more main model methods)
- Rework recipes, removing/hiding a lot of sections as a lot of recipes are incomplete with the current state of DML.


### Other changes

- Highlight fixes in some guides
- Remove feature flags guide
- Fix code block styles when there are no line numbers.

### Upcoming changes in other PRs

- Re-generate commerce module references (for the updates in the method names)
- Ensure that the data model references are generated correctly for models using DML.
- (probably at a very later point) revisit recipes

www/apps/book/app/advanced-development/api-routes/parameters/page.mdx

@@ -41,8 +41,8 @@ To create an API route that accepts multiple path parameters, create within the
 For example, create an API route at `src/api/store/hello-world/[id]/name/[name]/route.ts`:
 
 export const multiplePathHighlights = [
-  ["11", "req.params.id", "Access the path parameter `id`"],
-  ["11", "req.params.name", "Access the path parameter `name`"]
+  ["12", "req.params.id", "Access the path parameter `id`"],
+  ["13", "req.params.name", "Access the path parameter `name`"]
 ]
 
 ```ts title="src/api/store/hello-world/[id]/name/[name]/route.ts" highlights={multiplePathHighlights}
@@ -56,7 +56,9 @@ export const GET = (
   res: MedusaResponse
 ) => {
   res.json({
-    message: `[GET] Hello ${req.params.id} - ${req.params.name}!`,
+    message: `[GET] Hello ${
+      req.params.id
+    } - ${req.params.name}!`,
   })
 }
 ```