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/resources/app/commerce-modules/user/page.mdx

@@ -15,7 +15,7 @@ The User Module is the `@medusajs/user` NPM package that provides user-related f
 Manage and store your users through Create, Read, Update, and Delete (CRUD) operations:
 
 ```ts
-const user = await userModuleService.create({
+const user = await userModuleService.createUsers({
   email: "user@example.com",
   first_name: "John",
   last_name: "Smith",
@@ -65,7 +65,7 @@ For example:
       req.scope.resolve(ModuleRegistrationName.USER)
 
     res.json({
-      users: await userModuleService.list(),
+      users: await userModuleService.listUsers(),
     })
   }
   ```
@@ -84,7 +84,7 @@ For example:
     const userModuleService: IUserModuleService =
       container.resolve(ModuleRegistrationName.USER)
 
-    const users = await userModuleService.list()
+    const users = await userModuleService.listUsers()
   }
   ```
 
@@ -104,7 +104,7 @@ For example:
         ModuleRegistrationName.USER
       )
       
-    const users = await userModuleService.list()
+    const users = await userModuleService.listUsers()
   })
   ```