Improved documentation for "Serializers"

Author: bastianeicher

docs/serializers/bson.md

@@ -1,5 +1,7 @@
 # BSON
 
+BSON (Binary JSON) serialization is available in the .NET implementation of TypedRest.
+
 === "C#"
 
     The BSON serializer provides efficient binary serialization using [Newtonsoft.Json](https://www.newtonsoft.com/json)'s BSON support:
@@ -16,3 +18,7 @@
     - String enums with camel-case naming
     - Null values are not serialized
     - Automatic type name handling
+
+## Content type
+
+TODO: The serializer handles the `application/bson` content type.

docs/serializers/json.md

@@ -101,3 +101,7 @@ JSON is the default serialization format in TypedRest.
         new URL("http://example.com/"),
         new MySerializer());
     ```
+
+## Content type
+
+TODO: TypedRest automatically handle custom media types that end with `+json` (e.g., `application/vnd.api+json`, `application/hal+json`). These are treated as JSON and deserialized using the configured JSON serializer.

docs/serializers/xml.md

@@ -1,8 +1,19 @@
 # XML
 
+XML serialization is available in the .NET implementation of TypedRest.
+
 === "C#"
+    TODO: The XML serializer uses .NET's built-in `System.Xml.Serialization.XmlSerializer`:
+
     ```csharp
     var endpoint = new EntryEndpoint(
         new Uri("http://example.com/"),
         serializer: new XmlSerializer());
     ```
+
+## Content type
+
+TODO: The serializer handles the following content types:
+
+- `application/xml`
+- `text/xml`