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/inventory/concepts/page.mdx

@@ -20,15 +20,15 @@ The `InventoryItem` data model mainly holds details related to the underlying st
 
 An inventory level, represented by the [InventoryLevel data model](/references/inventory/models/InventoryLevel), holds the inventory and quantity details of an inventory item in a specific location.
 
-It has three quantity-related fields:
+It has three quantity-related properties:
 
 - `stocked_quantity`: The available stock quantity of an item in the associated location.
 - `reserved_quantity`: The quantity reserved from the available `stocked_quantity`. It indicates the quantity that's still not removed from stock, but considered as unavailable when checking whether an item is in stock.
-- `incoming_quantity`: The incoming stock quantity of an item into the associated location. This field doesn't play into the `stocked_quantity` or when checking whether an item is in stock.
+- `incoming_quantity`: The incoming stock quantity of an item into the associated location. This property doesn't play into the `stocked_quantity` or when checking whether an item is in stock.
 
 ### Associated Location
 
-The inventory level's location is determined by the `location_id` field. Medusa links the `InventoryLevel` data model with the `StockLocation` data model from the Stock Location Module.
+The inventory level's location is determined by the `location_id` property. Medusa links the `InventoryLevel` data model with the `StockLocation` data model from the Stock Location Module.
 
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