chore(deps): drop unused npm-check-updates devDep to clear tar alerts (#1306)

## Summary

Resolves the remaining 6 high-severity Dependabot alerts for `tar` on
the default branch. `tar@6.2.1` was being pulled in transitively via
`npm-check-updates@16 -> pacote@15 / cacache -> tar@^6`, and
Dependabot's `<= 7.5.10` ranges include 6.x semver-wise. Since
`npm-check-updates` was declared as a `devDependency` but never actually
invoked anywhere (no script, CI workflow, or doc references it),
removing it entirely is cleaner than bumping it — alerts cleared with
zero risk of regression.

After removal, the lock contains only `tar@7.5.12`, which satisfies all
six advisories.

## Test plan

- [x] `pnpm run lint` (js-sdk + cli)
- [x] `pnpm run typecheck` (js-sdk + cli)
- [x] `pnpm run format` (js-sdk + cli)
- [x] tar-related unit tests pass (`tests/template/utils`,
`tests/template/uploadFile` — 54 tests)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>

packages/js-sdk/package.json

@@ -58,7 +58,6 @@
     "json-schema-to-typescript": "^15.0.4",
     "knip": "^5.43.6",
     "msw": "^2.12.10",
-    "npm-check-updates": "^16.14.20",
     "npm-run-all": "^4.1.5",
     "openapi-typescript": "^7.9.1",
     "playwright": "^1.55.1",