test: skip auto-format in edit tests via setFormatCache helper

- Add setFormatCache() to auto-format.ts for test overrides
- Use setFormatCache(null) in edit-languages and edit-stack tests
  to prevent format detection from interfering with test assertions

Co-Authored-By: SoulForge <[email protected]>

src/core/tools/auto-format.ts

@@ -22,6 +22,11 @@ export function resetFormatCache(): void {
   cachedFormatCmd = undefined;
 }
 
+/** Override cached format command (e.g. set to null in tests to skip formatting). */
+export function setFormatCache(cmd: string | null): void {
+  cachedFormatCmd = cmd;
+}
+
 /**
  * Auto-format a file after edit. Returns true if formatted, false if skipped/failed.
  * Uses cached format command to avoid re-detecting project profile on every edit.

tests/edit-languages.test.ts

@@ -2,6 +2,7 @@ import { describe, expect, it, beforeEach, afterAll } from "bun:test";
 import { clearEditStacks, undoEditTool } from "../src/core/tools/edit-stack.js";
 import { editFileTool } from "../src/core/tools/edit-file.js";
 import { multiEditTool } from "../src/core/tools/multi-edit.js";
+import { setFormatCache } from "../src/core/tools/auto-format.js";
 import { writeFile, mkdir, rm } from "node:fs/promises";
 import { join } from "node:path";
 import { tmpdir } from "node:os";
@@ -16,6 +17,7 @@ async function writeTestFile(name: string, content: string): Promise<string> {
 
 beforeEach(async () => {
 	clearEditStacks();
+	setFormatCache(null);
 	await mkdir(TMP, { recursive: true });
 });
 

tests/edit-stack.test.ts

@@ -7,6 +7,7 @@ import {
 } from "../src/core/tools/edit-stack.js";
 import { editFileTool, buildRichEditError } from "../src/core/tools/edit-file.js";
 import { multiEditTool } from "../src/core/tools/multi-edit.js";
+import { setFormatCache } from "../src/core/tools/auto-format.js";
 import { writeFile, mkdir, rm } from "node:fs/promises";
 import { join } from "node:path";
 import { tmpdir } from "node:os";
@@ -21,6 +22,7 @@ async function writeTestFile(name: string, content: string): Promise<string> {
 
 beforeEach(async () => {
 	clearEditStacks();
+	setFormatCache(null);
 	await mkdir(TMP, { recursive: true });
 });