docs(typescript): add section on InferRawDocType to TypeScript docs

Author: vkarpov15

docs/typescript/schemas.md

@@ -9,7 +9,7 @@ Mongoose can automatically infer the document type from your schema definition a
 We recommend relying on automatic type inference when defining schemas and models.
 
 ```typescript
-import { Schema } from 'mongoose';
+import { Schema, model } from 'mongoose';
 // Schema
 const schema = new Schema({
   name: { type: String, required: true },
@@ -32,6 +32,31 @@ There are a few caveats for using automatic type inference:
 2. You need to define your schema in the `new Schema()` call. Don't assign your schema definition to a temporary variable. Doing something like `const schemaDefinition = { name: String }; const schema = new Schema(schemaDefinition);` will not work.
 3. Mongoose adds `createdAt` and `updatedAt` to your schema if you specify the `timestamps` option in your schema, *except* if you also specify `methods`, `virtuals`, or `statics`. There is a [known issue](https://github.com/Automattic/mongoose/issues/12807) with type inference with timestamps and methods/virtuals/statics options. If you use methods, virtuals, and statics, you're responsible for adding `createdAt` and `updatedAt` to your schema definition.
 
+If you need to explicitly get the raw document type (the value returned from `doc.toObject()`, `await Model.findOne().lean()`, etc.) from your schema definition, you can use Mongoose's `inferRawDocType` helper as follows:
+
+```ts
+import { Schema, InferRawDocType, model } from 'mongoose';
+
+const schemaDefinition = {
+  name: { type: String, required: true },
+  email: { type: String, required: true },
+  avatar: String
+} as const;
+const schema = new Schema(schemaDefinition);
+
+const UserModel = model('User', schema);
+const doc = new UserModel({ name: 'test', email: 'test' });
+
+type RawUserDocument = InferRawDocType<typeof schemaDefinition>;
+
+useRawDoc(doc.toObject());
+
+function useRawDoc(doc: RawUserDocument) {
+  // ...
+}
+
+```
+
 If automatic type inference doesn't work for you, you can always fall back to document interface definitions.
 
 ## Separate document interface definition