fix(backend): add env var test coverage and fix stale comments

- Add CLAUDE_CODE_DISABLE_EXPERIMENTAL_BETAS assertion in env_test.py
- Fix stale references to service.py → build_sdk_env() in env.py

autogpt_platform/backend/backend/copilot/sdk/cli_openrouter_compat_test.py

@@ -482,8 +482,8 @@ async def test_disable_experimental_betas_env_var_strips_headers():
     OpenRouter).
 
     This is the main regression guard: the env var is injected by
-    ``service.py`` into every CLI subprocess so newer SDK / CLI versions
-    work with OpenRouter without any proxy.
+    ``build_sdk_env()`` in ``env.py`` into every CLI subprocess so newer
+    SDK / CLI versions work with OpenRouter without any proxy.
     """
     returncode, _stdout, stderr, captured = await _run_reproduction(
         extra_env={"CLAUDE_CODE_DISABLE_EXPERIMENTAL_BETAS": "1"},

autogpt_platform/backend/backend/copilot/sdk/env_test.py

@@ -123,6 +123,8 @@ class TestBuildSdkEnvOpenRouter:
         assert result["ANTHROPIC_AUTH_TOKEN"] == "sk-or-test-key"
         assert result["ANTHROPIC_API_KEY"] == ""
         assert "ANTHROPIC_CUSTOM_HEADERS" not in result
+        # OpenRouter compat: env var must always be present
+        assert result.get("CLAUDE_CODE_DISABLE_EXPERIMENTAL_BETAS") == "1"
 
     def test_strips_trailing_v1(self):
         """The /v1 suffix is stripped from the base URL."""

autogpt_platform/backend/backend/copilot/sdk/sdk_compat_test.py

@@ -206,7 +206,7 @@ def test_sdk_exports_hook_event_type(hook_event: str):
 # features incompatible with OpenRouter (``tool_reference`` content
 # blocks, ``context-management-2025-06-27`` beta).  We neutralise these
 # at runtime by injecting ``CLAUDE_CODE_DISABLE_EXPERIMENTAL_BETAS=1``
-# into the CLI subprocess env (see ``service.py``).
+# into the CLI subprocess env (see ``build_sdk_env()`` in ``env.py``).
 #
 # This test is the cheapest possible regression guard: it pins the
 # bundled CLI to a known-good version.  If anyone bumps