fix: Resolve 4 CI failures — test mocks, assertions, and bandit suppressions

- Egress proxy tunnel test: use IP literal 127.0.0.1 instead of localhost
  to avoid IPv6 resolution mismatch in CI
- Batch upload mock: add missing is_read_only param to fake_store
- Client-replay test: allow inherited file refs in exec response (matches
  LibreChat CodeExecutor.ts contract)
- Bandit B103: suppress intentional 0o1777 chmod on shared skill-deps dir

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: usnavy13

src/api/admin.py

@@ -302,7 +302,7 @@ async def purge_skill_deps(_: str = Depends(verify_master_key)):
 
     # Reset perms so future installs from sandbox uids work.
     try:
-        os.chmod(str(deps_root), 0o1777)
+        os.chmod(str(deps_root), 0o1777)  # nosec B103
     except OSError:
         pass
 

src/main.py

@@ -160,7 +160,7 @@ async def _startup_egress_proxy(app: FastAPI) -> None:
         # Sticky + world-writable, like /tmp. The sandbox uid (e.g. 1001) needs
         # to write here; keeping it sticky means one sandbox can't unlink
         # another's files.
-        os.chmod(str(deps_root), 0o1777)
+        os.chmod(str(deps_root), 0o1777)  # nosec B103
     except OSError as exc:
         logger.warning(
             "Could not prepare skill-deps directory; "

tests/functional/test_client_replay.py

@@ -140,7 +140,8 @@ async def test_uploaded_files_follow_runtime_session_when_first_exec_has_no_outp
             injected_files=upload_refs,
         )
         assert "a,b" in first["stdout"]
-        assert first["files"] == []
+        generated = [f for f in first["files"] if not f.get("inherited")]
+        assert generated == [], f"Expected no generated files, got: {generated}"
 
         second = await _exec_like_runtime(
             async_client,

tests/integration/test_librechat_compat.py

@@ -1901,7 +1901,7 @@ def setup_mocks(self):
         stored_filenames = []
 
         async def fake_store(
-            session_id, filename, content, content_type, is_agent_file
+            session_id, filename, content, content_type, is_agent_file, is_read_only=False
         ):
             stored_filenames.append(filename)
             return f"fid-{len(stored_filenames)}"

tests/unit/test_egress_proxy.py

@@ -211,11 +211,11 @@ async def echo_handler(reader, writer):
     echo_server = await asyncio.start_server(echo_handler, "127.0.0.1", echo_port)
 
     proxy_port = _free_port()
-    proxy = EgressProxy(port=proxy_port, allowlist={"localhost"})
+    proxy = EgressProxy(port=proxy_port, allowlist={"127.0.0.1"})
     await proxy.start()
     try:
         status, reader, writer = await _send_connect(
-            proxy_port, f"localhost:{echo_port}"
+            proxy_port, f"127.0.0.1:{echo_port}"
         )
         assert b"200" in status, status