feat(agents): add OmO orchestrator agent

- Add OmO agent: powerful AI orchestrator for complex task delegation
- Implements parallel background agent execution and todo-driven workflows
- Emphasizes aggressive subagent delegation with 7-section prompt structure

Co-authored-by: huynguyen03dev <huynguyen03dev@users.noreply.github.com>
🤖 GENERATED WITH ASSISTANCE OF [OhMyOpenCode](https://github.com/code-yeongyu/oh-my-opencode)

src/agents/utils.ts

@@ -1,5 +1,6 @@
 import type { AgentConfig } from "@opencode-ai/sdk"
 import type { BuiltinAgentName, AgentOverrideConfig, AgentOverrides } from "./types"
+import { omoAgent } from "./omo"
 import { oracleAgent } from "./oracle"
 import { librarianAgent } from "./librarian"
 import { exploreAgent } from "./explore"
@@ -9,6 +10,7 @@ import { multimodalLookerAgent } from "./multimodal-looker"
 import { deepMerge } from "../shared"
 
 const allBuiltinAgents: Record<BuiltinAgentName, AgentConfig> = {
+  OmO: omoAgent,
   oracle: oracleAgent,
   librarian: librarianAgent,
   explore: exploreAgent,