refactor(tests): convert lazy require calls to static ES6 imports

- Convert json.test.ts: hoist fs/os/path imports and safeDelete/getEditableJsonClass to top-level
- Convert strings.test.ts: remove redundant require calls (already imported)
- Convert dlx/package.test.ts: add readFileSync to imports, remove inline requires
- Improves consistency with ES6 module patterns
- Better for tree-shaking and static analysis

Author: jdalton

test/unit/dlx/package.test.ts

@@ -11,7 +11,7 @@
  */
 
 import { createHash } from 'node:crypto'
-import { existsSync, mkdirSync, writeFileSync } from 'node:fs'
+import { existsSync, mkdirSync, readFileSync, writeFileSync } from 'node:fs'
 import path from 'node:path'
 import { describe, expect, it } from 'vitest'
 
@@ -567,10 +567,7 @@ describe('dlx-package', () => {
         // Reading package.json should work but bin field is missing
         expect(existsSync(path.join(nodeModules, 'package.json'))).toBe(true)
         const pkg = JSON.parse(
-          require('node:fs').readFileSync(
-            path.join(nodeModules, 'package.json'),
-            'utf8',
-          ),
+          readFileSync(path.join(nodeModules, 'package.json'), 'utf8'),
         )
         expect(pkg.bin).toBeUndefined()
       }, 'dlx-pkg-missing-')
@@ -602,10 +599,7 @@ describe('dlx-package', () => {
         // Should auto-select the single binary
         expect(existsSync(path.join(nodeModules, 'cli.js'))).toBe(true)
         const pkg = JSON.parse(
-          require('node:fs').readFileSync(
-            path.join(nodeModules, 'package.json'),
-            'utf8',
-          ),
+          readFileSync(path.join(nodeModules, 'package.json'), 'utf8'),
         )
         expect(typeof pkg.bin).toBe('string')
         expect(pkg.bin).toBe('./cli.js')
@@ -658,10 +652,7 @@ describe('dlx-package', () => {
 
         // Should find the binary matching last segment of package name
         const pkg = JSON.parse(
-          require('node:fs').readFileSync(
-            path.join(nodeModules, 'package.json'),
-            'utf8',
-          ),
+          readFileSync(path.join(nodeModules, 'package.json'), 'utf8'),
         )
         expect(pkg.bin['multi-bin']).toBe('./bin/main.js')
 
@@ -706,10 +697,7 @@ describe('dlx-package', () => {
 
         // Should fall back to first binary (other-a)
         const pkg = JSON.parse(
-          require('node:fs').readFileSync(
-            path.join(nodeModules, 'package.json'),
-            'utf8',
-          ),
+          readFileSync(path.join(nodeModules, 'package.json'), 'utf8'),
         )
         const firstBinary = Object.keys(pkg.bin)[0]
         expect(firstBinary).toBe('other-a')

test/unit/json.test.ts

@@ -13,6 +13,12 @@
  * including empty strings, special characters, unicode, and very large JSON payloads.
  */
 
+import { mkdtemp, readFile, writeFile } from 'node:fs/promises'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+
+import { safeDelete } from '@socketsecurity/lib/fs'
+import { getEditableJsonClass } from '@socketsecurity/lib/json/edit'
 import { isJsonPrimitive, jsonParse } from '@socketsecurity/lib/json/parse'
 import { afterEach, beforeEach, describe, expect, it } from 'vitest'
 
@@ -752,14 +758,6 @@ describe('json', () => {
   })
 
   describe('EditableJson', () => {
-    const { tmpdir } = require('node:os')
-    const { join } = require('node:path')
-    const { mkdtemp, readFile, writeFile } = require('node:fs/promises')
-    const { safeDelete } =
-      require('@socketsecurity/lib/fs') as typeof import('@socketsecurity/lib/fs')
-    const { getEditableJsonClass } =
-      require('@socketsecurity/lib/json/edit') as typeof import('@socketsecurity/lib/json/edit')
-
     let testDir: string
 
     beforeEach(async () => {

test/unit/strings.test.ts

@@ -448,12 +448,10 @@ describe('strings', () => {
 
   describe('fromCharCode', () => {
     it('should be exported', () => {
-      const { fromCharCode } = require('@socketsecurity/lib/strings')
       expect(typeof fromCharCode).toBe('function')
     })
 
     it('should convert char codes to strings', () => {
-      const { fromCharCode } = require('@socketsecurity/lib/strings')
       expect(fromCharCode(65)).toBe('A')
       expect(fromCharCode(97)).toBe('a')
       expect(fromCharCode(48)).toBe('0')