Misc tool tweaks (#35734)

Some minor tooling tweaks:

- Ignore .venv in golangci-lint
- Move go tools to tools directory (e.g. everything that is not "build")
- Enable reportUnusedInlineConfigs in eslint, no current violations
- Apply modernize fix in code-batch-process, modernize cli did
apparently not catch it because of the `go:build ignore` tag.

eslint.config.ts

@@ -49,6 +49,7 @@ export default defineConfig([
     },
     linterOptions: {
       reportUnusedDisableDirectives: 2,
+      reportUnusedInlineConfigs: 2,
     },
     plugins: {
       '@eslint-community/eslint-comments': comments,