refactor(parser): Improve ALB models with examples and descriptions

aws_lambda_powertools/utilities/parser/models/alb.py

@@ -1,21 +1,48 @@
 from typing import Dict, Type, Union
 
-from pydantic import BaseModel
+from pydantic import BaseModel, Field
 
 
 class AlbRequestContextData(BaseModel):
-    targetGroupArn: str
+    targetGroupArn: str = Field(
+        description="The ARN of the target group that the request was routed to.",
+        examples=[
+            "arn:aws:elasticloadbalancing:us-east-1:123456789012:targetgroup/my-targets/73e2d6bc24d8a067",
+            "arn:aws:elasticloadbalancing:eu-west-1:123456789012:targetgroup/api-targets/1234567890123456",
+        ],
+    )
 
 
 class AlbRequestContext(BaseModel):
-    elb: AlbRequestContextData
+    elb: AlbRequestContextData = Field(
+        description="Information about the Elastic Load Balancer that processed the request.",
+    )
 
 
 class AlbModel(BaseModel):
-    httpMethod: str
-    path: str
-    body: Union[str, Type[BaseModel]]
-    isBase64Encoded: bool
-    headers: Dict[str, str]
-    queryStringParameters: Dict[str, str]
-    requestContext: AlbRequestContext
+    httpMethod: str = Field(
+        description="The HTTP method used for the request.",
+        examples=["GET", "POST", "PUT", "DELETE", "PATCH", "HEAD", "OPTIONS", "CONNECT"],
+    )
+    path: str = Field(
+        description="The path portion of the request URL.",
+        examples=["/", "/api/users", "/health", "/api/v1/products/123"],
+    )
+    body: Union[str, Type[BaseModel]] = Field(
+        description="The request body. Can be a string or a parsed model if content-type allows parsing.",
+    )
+    isBase64Encoded: bool = Field(description="Indicates whether the body is base64-encoded.", examples=[False, True])
+    headers: Dict[str, str] = Field(
+        description="The request headers as key-value pairs.",
+        examples=[
+            {"host": "example.com", "user-agent": "Mozilla/5.0"},
+            {"content-type": "application/json", "authorization": "Bearer token123"},
+        ],
+    )
+    queryStringParameters: Dict[str, str] = Field(
+        description="The query string parameters as key-value pairs.",
+        examples=[{"page": "1", "limit": "10"}, {"filter": "active", "sort": "name"}],
+    )
+    requestContext: AlbRequestContext = Field(
+        description="Contains information about the request context, including the load balancer details.",
+    )