Refactor setup and tool helpers for improved modularity and clarity

- Moved setup logic into dedicated files: agent.ts, config.ts, index.ts, workspace.ts.
- Introduced tool-helpers.ts for shared functions across tools, reducing boilerplate.
- Updated tools (status, task-comment, task-create, task-update, work-finish, work-start) to utilize new helper functions for workspace resolution and provider creation.
- Enhanced error handling and context detection in tools.
- Improved project resolution logic to streamline tool execution.
- Added new functionality for agent creation and configuration management in setup.

lib/cli.ts

@@ -4,7 +4,7 @@
  * Uses Commander.js (provided by OpenClaw plugin SDK context).
  */
 import type { Command } from "commander";
-import { runSetup } from "./setup.js";
+import { runSetup } from "./setup/index.js";
 import { ALL_TIERS, DEFAULT_MODELS, type Tier } from "./tiers.js";
 
 /**