feat(migration): implement workspace layout migration and testing

- Added `migrate-layout.ts` to handle migration from old workspace layouts to the new `devclaw/` structure.
- Introduced `migrate-layout.test.ts` for comprehensive tests covering various migration scenarios.
- Updated `workspace.ts` to ensure default files are created post-migration, including `workflow.yaml` and role-specific prompts.
- Refactored role instruction handling to accommodate new directory structure.
- Enhanced project registration to scaffold prompt files in the new `devclaw/projects/<project>/prompts/` directory.
- Adjusted setup tool descriptions and logic to reflect changes in file structure.
- Updated templates to align with the new workflow configuration and role instructions.

lib/audit.ts

@@ -5,6 +5,7 @@
  */
 import { appendFile, mkdir, readFile, writeFile } from "node:fs/promises";
 import { join, dirname } from "node:path";
+import { DATA_DIR } from "./setup/migrate-layout.js";
 
 const MAX_LOG_LINES = 50;
 
@@ -13,7 +14,7 @@ export async function log(
   event: string,
   data: Record<string, unknown>,
 ): Promise<void> {
-  const filePath = join(workspaceDir, "log", "audit.log");
+  const filePath = join(workspaceDir, DATA_DIR, "log", "audit.log");
   const entry = JSON.stringify({
     ts: new Date().toISOString(),
     event,