feat: add thread list and deletion API with new component

- switch docs, stories, and UI to the slot-based CopilotThreadList API
- surface delete controls with optimistic updates and error feedback
- extend useThreads with deleteThread/currentThreadId helpers plus tests
- prevent suggestion-generated runs from polluting thread history
- wire DELETE handler through runtime endpoints and runner backends
- harden CopilotChat reconnect flow and tool-call rendering keys

Signed-off-by: Tyler Slaton <tyler@copilotkit.ai>

Author: tylerslaton

apps/docs/docs.json

@@ -40,6 +40,13 @@
         "group": "Get Started",
         "pages": ["introduction"]
       },
+      {
+        "group": "Guides",
+        "pages": [
+          "guides/resource-scoping",
+          "guides/thread-management"
+        ]
+      },
       {
         "group": "API Reference",
         "pages": [