Prevent settings-profile Claude launches from reintroducing
routing/auth env after the final env merge.
- re-strip ANTHROPIC_BASE_URL, ANTHROPIC_AUTH_TOKEN, and
ANTHROPIC_API_KEY after merging envVars
- preserve model-selection env such as ANTHROPIC_MODEL and
ANTHROPIC_DEFAULT_SONNET_MODEL
- add a regression test covering explicit settings-profile
overrides that try to reintroduce routing env
Verification:
- bun test tests/unit/utils/claudecode-env-stripping.test.ts
- bun run validate