feat(acp): introduce threads (#8344)

Signed-off-by: Bradley Axen <baxen@squareup.com>

ui/desktop/openapi.json

@@ -7748,6 +7748,10 @@
           "session_type": {
             "$ref": "#/components/schemas/SessionType"
           },
+          "thread_id": {
+            "type": "string",
+            "nullable": true
+          },
           "total_tokens": {
             "type": "integer",
             "format": "int32",

ui/desktop/src/api/types.gen.ts

@@ -1232,6 +1232,7 @@ export type Session = {
     recipe?: Recipe | null;
     schedule_id?: string | null;
     session_type?: SessionType;
+    thread_id?: string | null;
     total_tokens?: number | null;
     updated_at: string;
     user_recipe_values?: {