Add required fields to multiple schema overrides (#357)

Adds required field arrays to 14 schemas that were missing them,
causing Fern to generate all properties as Optional<T> in the Java SDK.

Schemas updated:
- conversation_rating, conversation_part, conversation_part_author
- ticket_part, ticket_part_author
- segment, team, conversation_source, linked_object
- news_item, newsfeed, newsfeed_assignment
- help_center, part_attachment

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: mailsongabriel

fern/openapi-overrides.yml

@@ -2223,6 +2223,106 @@ components:
     update_company_request:
       x-fern-type-name: UpdateCompanyRequestBody
 
+    conversation_rating:
+      required:
+        - rating
+        - created_at
+
+    conversation_part:
+      required:
+        - type
+        - id
+        - part_type
+        - created_at
+        - updated_at
+        - author
+        - redacted
+
+    conversation_part_author:
+      required:
+        - type
+        - id
+
+    ticket_part:
+      required:
+        - type
+        - id
+        - part_type
+        - created_at
+        - updated_at
+        - author
+        - redacted
+
+    ticket_part_author:
+      required:
+        - type
+        - id
+
+    segment:
+      required:
+        - type
+        - id
+        - name
+        - created_at
+        - updated_at
+        - person_type
+
+    team:
+      required:
+        - type
+        - id
+        - name
+        - admin_ids
+
+    conversation_source:
+      required:
+        - type
+        - id
+        - delivered_as
+        - author
+        - redacted
+
+    linked_object:
+      required:
+        - type
+        - id
+
+    news_item:
+      required:
+        - type
+        - id
+        - workspace_id
+        - title
+        - state
+        - created_at
+        - updated_at
+
+    newsfeed:
+      required:
+        - type
+        - id
+        - name
+        - created_at
+        - updated_at
+
+    newsfeed_assignment:
+      required:
+        - newsfeed_id
+
+    help_center:
+      required:
+        - id
+        - workspace_id
+        - created_at
+        - updated_at
+        - identifier
+
+    part_attachment:
+      required:
+        - type
+        - name
+        - url
+
   securitySchemes:
     bearerAuth:
       x-fern-bearer: