refactor(tests): use createEnvProxy from socket-lib

Import createEnvProxy from @socketsecurity/lib/env instead of
defining locally. This standardizes the approach and makes the
helper available to all Socket projects.

Benefits:
- Reduces code duplication
- Maintains single source of truth in socket-lib
- Other projects can now use the same helper
- Better documented and tested in socket-lib

Related: socket-lib commit 3014e7f

Author: jdalton

packages/cli/test/utils.mts

@@ -3,6 +3,7 @@ import { fileURLToPath } from 'node:url'
 
 import { it } from 'vitest'
 
+import { createEnvProxy } from '@socketsecurity/lib/env'
 import { type SpawnOptions, spawn } from '@socketsecurity/lib/spawn'
 import { stripAnsi } from '@socketsecurity/lib/strings'
 
@@ -24,145 +25,6 @@ if (!process.env['VITEST']) {
   process.env['VITEST'] = '1'
 }
 
-/**
- * Create a case-insensitive environment variable Proxy for Windows compatibility.
- * On Windows, environment variables are case-insensitive (PATH vs Path vs path).
- * This Proxy provides consistent access regardless of case, with priority given
- * to exact matches, then case-insensitive matches for known vars.
- *
- * @param base - Base environment object (usually process.env)
- * @param overrides - Optional overrides to merge
- * @returns Proxy that handles case-insensitive env var access
- */
-function createEnvProxy(
-  base: NodeJS.ProcessEnv,
-  overrides?: Record<string, string | undefined>,
-): NodeJS.ProcessEnv {
-  // Common environment variables that have case sensitivity issues on Windows.
-  const caseInsensitiveKeys = new Set([
-    'PATH',
-    'TEMP',
-    'TMP',
-    'HOME',
-    'USERPROFILE',
-    'APPDATA',
-    'LOCALAPPDATA',
-    'PROGRAMFILES',
-    'SYSTEMROOT',
-    'WINDIR',
-  ])
-
-  return new Proxy(
-    {},
-    {
-      get(_target, prop) {
-        if (typeof prop !== 'string') {
-          return undefined
-        }
-
-        // Priority 1: Check overrides for exact match.
-        if (overrides && prop in overrides) {
-          return overrides[prop]
-        }
-
-        // Priority 2: Check base for exact match.
-        if (prop in base) {
-          return base[prop]
-        }
-
-        // Priority 3: Case-insensitive lookup for known keys.
-        const upperProp = prop.toUpperCase()
-        if (caseInsensitiveKeys.has(upperProp)) {
-          // Check overrides with case variations.
-          if (overrides) {
-            for (const key of Object.keys(overrides)) {
-              if (key.toUpperCase() === upperProp) {
-                return overrides[key]
-              }
-            }
-          }
-          // Check base with case variations.
-          for (const key of Object.keys(base)) {
-            if (key.toUpperCase() === upperProp) {
-              return base[key]
-            }
-          }
-        }
-
-        return undefined
-      },
-
-      ownKeys(_target) {
-        const keys = new Set<string>([
-          ...Object.keys(base),
-          ...(overrides ? Object.keys(overrides) : []),
-        ])
-        return [...keys]
-      },
-
-      getOwnPropertyDescriptor(_target, prop) {
-        if (typeof prop !== 'string') {
-          return undefined
-        }
-
-        // Use the same lookup logic as get().
-        const value = this.get?.(_target, prop, _target)
-        return value !== undefined
-          ? {
-              enumerable: true,
-              configurable: true,
-              writable: true,
-              value,
-            }
-          : undefined
-      },
-
-      has(_target, prop) {
-        if (typeof prop !== 'string') {
-          return false
-        }
-
-        // Check overrides.
-        if (overrides && prop in overrides) {
-          return true
-        }
-
-        // Check base.
-        if (prop in base) {
-          return true
-        }
-
-        // Case-insensitive check.
-        const upperProp = prop.toUpperCase()
-        if (caseInsensitiveKeys.has(upperProp)) {
-          if (overrides) {
-            for (const key of Object.keys(overrides)) {
-              if (key.toUpperCase() === upperProp) {
-                return true
-              }
-            }
-          }
-          for (const key of Object.keys(base)) {
-            if (key.toUpperCase() === upperProp) {
-              return true
-            }
-          }
-        }
-
-        return false
-      },
-
-      set(_target, prop, value) {
-        if (typeof prop === 'string' && overrides) {
-          overrides[prop] = value
-          return true
-        }
-        return false
-      },
-    },
-  ) as NodeJS.ProcessEnv
-}
-
 // Backward compatibility object for tests.
 // In VITEST mode, use a Proxy to keep env vars live and handle case-sensitivity.
 const constants = {