test(infra): retry recursive temp-dir removal on main (main twin of #11968)

`main` has been red since b342c1a361 on the vitest and integration gates:

  ✖ tests/unit/autoCombo/provider-family-combos.test.ts > auto/<family>
  ✖ chat pipeline applies Codex OAuth fingerprint and priority tier inside combos

Both call resetStorage() from beforeEach, which does an fs.rmSync(TEST_DATA_DIR,
{recursive: true, force: true}) with no retry, and intermittently loses the race
with a not-yet-released SQLite handle (ENOTEMPTY).

release/v3.8.51 fixed this in #11968 with a mechanical codemod adding
maxRetries/retryDelay to every recursive rm/rmSync/rmdirSync under tests/, but
that PR landed only on the release branch. Because main only receives work at
the release squash, it stayed broken for the whole cycle — and repo-wide gates
then turn every open PR into main red on checks unrelated to their diff.

This is the --base main twin: re-runs the same codemod that already shipped on
the release branch (scripts/ad-hoc/codemod-rm-maxretries.mjs), so the two
branches converge on identical test-teardown semantics. Test-only; no product
logic is touched.

The remaining three failures reported on #12133 (unit full suite exceeding its
4800s ceiling, package-artifact exceeding 1200s, and the boot-smoke that is
skipped as a consequence) are runner-contention timeouts, not code defects —
validate-release-green.mjs runs those heavy gates concurrently on one shared
hosted runner. There is no fix to port for those.

tests/unit/cli-setup-opencode.test.ts

@@ -62,7 +62,7 @@ describe("omniroute setup opencode", () => {
     console.info = _console.info;
     console.warn = _console.warn;
     try {
-      fs.rmSync(FIXTURE_ROOT, { recursive: true, force: true });
+      fs.rmSync(FIXTURE_ROOT, { recursive: true, force: true, maxRetries: 5, retryDelay: 100 });
     } catch {
       // best-effort temp cleanup
     }
@@ -146,7 +146,7 @@ describe("omniroute setup opencode", () => {
   });
 
   it("fails with a clear error (exit 1) when the bundled plugin dist is missing", async () => {
-    fs.rmSync(path.join(FAKE_PLUGIN_DIR, "dist"), { recursive: true, force: true });
+    fs.rmSync(path.join(FAKE_PLUGIN_DIR, "dist"), { recursive: true, force: true, maxRetries: 5, retryDelay: 100 });
     try {
       const r = await runSetupOpenCodeCommand({
         configDir: CONFIG_DIR,