test(sync): strip CI env from --force e2e helpers

GitHub Actions and GitLab CI set CI=true, which the sync --force guard
in register-sync-root.ts checks before the TTY branch. Two tests were
inheriting CI=true via {...process.env, ...} and hitting the CI-guard
exit (6) instead of the branch they were written to cover:

  - cli-sync.e2e.test.ts "should retranslate with --force"
    runSyncAll('--force') -> execSync threw Command failed.
    Fix in the shared buildEnv() so every CI-neutral invocation in
    this file is unaffected by the runner's CI flag.

  - cli-sync-force-guard.e2e.test.ts "proceeds without prompting
    when stdin is not a TTY"
    Explicitly asserts status !== 6 for the piped-stdin / no-yes
    branch; CI-guard fired first. Strip CI only in that one case;
    the sibling "CI=true --force without --yes" test still sets
    CI=true explicitly.

Author: sjsyrek

tests/e2e/cli-sync-force-guard.e2e.test.ts

@@ -168,10 +168,13 @@ describe('deepl sync --force billing defense', () => {
 
   describe('non-TTY stdin (piped) without --yes', () => {
     it('proceeds without prompting when stdin is not a TTY', () => {
-      // spawnSync with input= sets stdin to a pipe, so isTTY is false
+      // spawnSync with input= sets stdin to a pipe, so isTTY is false.
+      // CI is stripped so the CI-guard branch does not pre-empt the TTY branch
+      // this test is designed to exercise (GitHub Actions / GitLab CI set CI=true).
+      const { CI: _ci, ...baseEnv } = process.env;
       const result = run(['--force', '--dry-run'], {
         cwd: tmpDir,
-        env: { ...process.env, DEEPL_CONFIG_DIR: path.join(tmpDir, 'config'), NO_COLOR: '1' },
+        env: { ...baseEnv, DEEPL_CONFIG_DIR: path.join(tmpDir, 'config'), NO_COLOR: '1' },
         input: 'y\n',
       });
 

tests/e2e/cli-sync.e2e.test.ts

@@ -95,8 +95,13 @@ describe('CLI Sync E2E', () => {
   }
 
   function buildEnv(): Record<string, string | undefined> {
+    // Strip CI so the --force billing guard (register-sync-root.ts) does not
+    // fire its CI-without-yes branch when these tests run under GitHub Actions
+    // / GitLab CI. Individual tests that exercise CI semantics set CI=true
+    // explicitly.
+    const { CI: _ci, ...rest } = process.env;
     return {
-      ...process.env,
+      ...rest,
       DEEPL_CONFIG_DIR: testConfig.path,
       NO_COLOR: '1',
     };