test(env): fix CI test failures for getCI() on Ubuntu and Windows

Author: jdalton

test/unit/env/ci.test.mts

@@ -10,7 +10,7 @@
 
 import { getCI } from '@socketsecurity/lib/env/ci'
 import { clearEnv, resetEnv, setEnv } from '@socketsecurity/lib/env/rewire'
-import { afterEach, describe, expect, it } from 'vitest'
+import { afterEach, describe, expect, it, vi } from 'vitest'
 
 describe('env/ci', () => {
   afterEach(() => {
@@ -90,8 +90,11 @@ describe('env/ci', () => {
       setEnv('CI', 'true')
       expect(getCI()).toBe(true)
 
+      // On CI systems, process.env.CI exists, so stub it out first
+      vi.stubEnv('CI', undefined)
       clearEnv('CI')
       expect(getCI()).toBe(false)
+      vi.unstubAllEnvs()
     })
 
     it('should handle consecutive reads', () => {

test/unit/env/rewire.test.mts

@@ -56,9 +56,12 @@ describe('env rewiring', () => {
       setEnv('CI', '')
       expect(getCI()).toBe(true)
 
-      // CI returns false only when cleared
+      // CI returns false only when cleared AND not in process.env
+      // On CI systems, process.env.CI exists, so stub it out first
+      vi.stubEnv('CI', undefined)
       clearEnv('CI')
       expect(getCI()).toBe(false)
+      vi.unstubAllEnvs()
     })
 
     it('should allow undefined overrides', () => {
@@ -100,8 +103,11 @@ describe('env rewiring', () => {
       setEnv('CI', 'false')
       expect(getCI()).toBe(true) // Key exists, so true
 
+      // Clear both override and process.env (for CI systems where CI is set)
+      vi.stubEnv('CI', undefined)
       clearEnv('CI')
       expect(getCI()).toBe(false) // Key doesn't exist
+      vi.unstubAllEnvs()
     })
 
     it('test 3: should not be affected by previous tests', () => {