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/customer/examples/page.mdx

@@ -25,7 +25,7 @@ In this guide, you’ll find common examples of how you can use the Customer Mod
     const customerModuleService: ICustomerModuleService =
       request.scope.resolve(ModuleRegistrationName.CUSTOMER)
 
-    const customer = await customerModuleService.create({
+    const customer = await customerModuleService.createCustomers({
       first_name: "Peter",
       last_name: "Hayes",
       email: "peter.hayes@example.com",
@@ -50,7 +50,7 @@ In this guide, you’ll find common examples of how you can use the Customer Mod
   export async function POST(request: Request) {
     const customerModuleService = await initializeCustomerModule()
 
-    const customer = await customerModuleService.create({
+    const customer = await customerModuleService.createCustomers({
       first_name: "Peter",
       last_name: "Hayes",
       email: "peter.hayes@example.com",
@@ -85,7 +85,7 @@ In this guide, you’ll find common examples of how you can use the Customer Mod
       request.scope.resolve(ModuleRegistrationName.CUSTOMER)
 
     const customerGroup =
-      await customerModuleService.createCustomerGroup({
+      await customerModuleService.createCustomerGroups({
         name: "VIP",
       })
 
@@ -109,7 +109,7 @@ In this guide, you’ll find common examples of how you can use the Customer Mod
     const customerModuleService = await initializeCustomerModule()
 
     const customerGroup =
-      await customerModuleService.createCustomerGroup({
+      await customerModuleService.createCustomerGroups({
         name: "VIP",
       })