chore: fix all biome lint errors

- Auto-fix string concatenation → template literals
- Remove unused imports
- Prefix unused function with underscore
- Format fixes across multiple files

packages/workflow-execute/__tests__/merkle-call-stack.test.ts

@@ -14,7 +14,7 @@ import type {
 } from "@uncaged/workflow-runtime";
 
 import { executeThread } from "../src/engine/engine.js";
-import type { ExecuteThreadIo, ExecuteThreadOptions } from "../src/engine/types.js";
+import type { ExecuteThreadOptions } from "../src/engine/types.js";
 
 const TEST_REGISTRY_YAML = `config:
   maxDepth: 3

packages/workflow-execute/package.json

@@ -1,7 +1,10 @@
 {
   "name": "@uncaged/workflow-execute",
   "version": "0.3.16",
-  "files": ["dist", "package.json"],
+  "files": [
+    "dist",
+    "package.json"
+  ],
   "type": "module",
   "exports": {
     ".": {
@@ -27,4 +30,4 @@
   "devDependencies": {
     "zod": "^4.0.0"
   }
-}
+}

packages/workflow-execute/src/workflow-as-agent.ts

@@ -59,17 +59,26 @@ export function workflowAsAgent(
 
     const registryResult = await readWorkflowRegistry(storageRoot);
     if (!registryResult.ok) {
-      return { output: `ERROR: failed to read workflow registry: ${registryResult.error.message}`, childThread: null };
+      return {
+        output: `ERROR: failed to read workflow registry: ${registryResult.error.message}`,
+        childThread: null,
+      };
     }
 
     const maxDepth = workflowAsAgentMaxDepth(registryResult.value.config);
     if (nextDepth > maxDepth) {
-      return { output: `ERROR: workflow-as-agent depth limit exceeded (max ${maxDepth})`, childThread: null };
+      return {
+        output: `ERROR: workflow-as-agent depth limit exceeded (max ${maxDepth})`,
+        childThread: null,
+      };
     }
 
     const entry = getRegisteredWorkflow(registryResult.value, workflowName);
     if (entry === null) {
-      return { output: `ERROR: workflow "${workflowName}" not found in registry`, childThread: null };
+      return {
+        output: `ERROR: workflow "${workflowName}" not found in registry`,
+        childThread: null,
+      };
     }
 
     const bundlePath = join(storageRoot, "bundles", `${entry.hash}.esm.js`);