Raise agent heartbeat concurrency default

Co-Authored-By: Paperclip <noreply@paperclip.ing>

packages/shared/src/constants.ts

@@ -72,7 +72,7 @@ export const AGENT_ROLE_LABELS: Record<AgentRole, string> = {
   general: "General",
 };
 
-export const AGENT_DEFAULT_MAX_CONCURRENT_RUNS = 5;
+export const AGENT_DEFAULT_MAX_CONCURRENT_RUNS = 20;
 export const WORKSPACE_BRANCH_ROUTINE_VARIABLE = "workspaceBranch";
 
 export const MODEL_PROFILE_KEYS = ["cheap"] as const;