fix(agents): restore canonical core agent ordering

Remap the core agent keys, default agent, and command routing back to\nlist display names so OpenCode's name-based sorting keeps the\ncanonical Sisyphus -> Hephaestus -> Prometheus -> Atlas order.\n\nAlso teach tool config lookups to resolve the prefixed list keys and\nadd regression tests that exercise the real ordering and routing path.

src/plugin-handlers/tool-config-handler.ts

@@ -1,5 +1,5 @@
 import type { OhMyOpenCodeConfig } from "../config";
-import { getAgentDisplayName } from "../shared/agent-display-names";
+import { getAgentDisplayName, getAgentListDisplayName } from "../shared/agent-display-names";
 import { isTaskSystemEnabled } from "../shared";
 
 type AgentWithPermission = { permission?: Record<string, unknown> };
@@ -16,7 +16,7 @@ function getConfigQuestionPermission(): string | null {
 }
 
 function agentByKey(agentResult: Record<string, unknown>, key: string): AgentWithPermission | undefined {
-  return (agentResult[getAgentDisplayName(key)] ?? agentResult[key]) as
+  return (agentResult[getAgentListDisplayName(key)] ?? agentResult[getAgentDisplayName(key)] ?? agentResult[key]) as
     | AgentWithPermission
     | undefined;
 }