fix: migrate coding-agent tests from fs.rm to removeWithRetries

Migrate 203 test files (356 call sites) from fs.rm/fs.rmSync to
removeWithRetries/removeSyncWithRetries to reduce EBUSY test failures
on Windows. removeWithRetries is now exported from @oh-my-pi/pi-utils.

The migration uses a regex-based approach that:
- Replaces fs.rm(path, { recursive, force }) → removeWithRetries(path)
- Replaces fs.rmSync(path, { recursive, force }) → removeSyncWithRetries(path)
- Replaces fs.rm(path) → removeWithRetries(path) (no options)
- Skips fs.rm/fs.rmSync inside template literals (bun --eval scripts)
- Adds imports to existing @oh-my-pi/pi-utils import or creates new one
- Removes unused fs imports where fs.rm was the only fs usage (4 files)

packages/coding-agent/test/tools/fetch-binary-dispatch.test.ts

@@ -10,7 +10,7 @@ import { ReadTool } from "@oh-my-pi/pi-coding-agent/tools/read";
 import { zip } from "@oh-my-pi/pi-coding-agent/utils/zip";
 import * as scrapers from "@oh-my-pi/pi-coding-agent/web/scrapers/types";
 import * as scraperUtils from "@oh-my-pi/pi-coding-agent/web/scrapers/utils";
-import { Snowflake } from "@oh-my-pi/pi-utils";
+import { removeSyncWithRetries, Snowflake } from "@oh-my-pi/pi-utils";
 
 function makeSession(testDir: string): ToolSession {
 	const sessionFile = path.join(testDir, "session.jsonl");
@@ -108,7 +108,7 @@ describe("read URL binary dispatch", () => {
 
 	afterEach(() => {
 		vi.restoreAllMocks();
-		fs.rmSync(testDir, { recursive: true, force: true });
+		removeSyncWithRetries(testDir);
 	});
 
 	it("lists a remote zip instead of dumping decoded bytes", async () => {