chore: remove unused imports and dead locals (ruff F401, F841) (#17010)

Mechanical cleanup across 43 files — removes 46 unused imports
(F401) and 14 unused local variables (F841) detected by
`ruff check --select F401,F841`. Net: -49 lines.

Also fixes a latent NameError in rl_cli.py where `get_hermes_home()`
was called at module line 32 before its import at line 65 — the
module never imported successfully on main. The ruff audit surfaced
this because it correctly saw the symbol as imported-but-unused
(the call happened before the import ran); the fix moves the import
to the top of the file alongside other stdlib imports.

One `# noqa: F401` kept in hermes_cli/status.py for `subprocess`:
tests monkeypatch `hermes_cli.status.subprocess` as a regression
guard that systemctl isn't called on Termux, so the name must
exist at module scope even though the module body doesn't reference
it. Docstring explains the reason.

Also fixes an invalid `# noqa:` directive in
gateway/platforms/discord.py:308 that lacked a rule code.

Co-authored-by: teknium1 <teknium@users.noreply.github.com>

agent/anthropic_adapter.py

@@ -523,9 +523,6 @@ def _read_claude_code_credentials_from_keychain() -> Optional[Dict[str, Any]]:
 
     Returns dict with {accessToken, refreshToken?, expiresAt?} or None.
     """
-    import platform
-    import subprocess
-
     if platform.system() != "Darwin":
         return None
 

agent/credential_pool.py

@@ -7,7 +7,6 @@ import random
 import threading
 import time
 import uuid
-import os
 import re
 from dataclasses import dataclass, fields, replace
 from datetime import datetime

agent/credential_sources.py

@@ -47,7 +47,6 @@ from __future__ import annotations
 
 import os
 from dataclasses import dataclass, field
-from pathlib import Path
 from typing import Callable, List, Optional
 
 

agent/gemini_cloudcode_adapter.py

@@ -30,7 +30,6 @@ from __future__ import annotations
 
 import json
 import logging
-import os
 import time
 import uuid
 from types import SimpleNamespace
@@ -42,7 +41,6 @@ from agent import google_oauth
 from agent.gemini_schema import sanitize_gemini_tool_parameters
 from agent.google_code_assist import (
     CODE_ASSIST_ENDPOINT,
-    FREE_TIER_ID,
     CodeAssistError,
     ProjectContext,
     resolve_project_context,

agent/gemini_schema.py

@@ -2,7 +2,7 @@
 
 from __future__ import annotations
 
-from typing import Any, Dict, List
+from typing import Any, Dict
 
 # Gemini's ``FunctionDeclaration.parameters`` field accepts the ``Schema``
 # object, which is only a subset of OpenAPI 3.0 / JSON Schema.  Strip fields

agent/google_code_assist.py

@@ -29,7 +29,6 @@ from __future__ import annotations
 
 import json
 import logging
-import os
 import time
 import urllib.error
 import urllib.parse

agent/google_oauth.py

@@ -49,14 +49,13 @@ import json
 import logging
 import os
 import secrets
-import socket
 import stat
 import threading
 import time
 import urllib.error
 import urllib.parse
 import urllib.request
-from dataclasses import dataclass, field
+from dataclasses import dataclass
 from pathlib import Path
 from typing import Any, Dict, Optional, Tuple
 

agent/memory_manager.py

@@ -28,7 +28,6 @@ Usage in run_agent.py:
 
 from __future__ import annotations
 
-import json
 import logging
 import re
 import inspect

agent/transports/codex.py

@@ -8,7 +8,7 @@ streaming, or the _run_codex_stream() call path.
 from typing import Any, Dict, List, Optional
 
 from agent.transports.base import ProviderTransport
-from agent.transports.types import NormalizedResponse, ToolCall, Usage
+from agent.transports.types import NormalizedResponse, ToolCall
 
 
 class ResponsesApiTransport(ProviderTransport):
@@ -151,8 +151,6 @@ class ResponsesApiTransport(ProviderTransport):
         """Normalize Codex Responses API response to NormalizedResponse."""
         from agent.codex_responses_adapter import (
             _normalize_codex_response,
-            _extract_responses_message_text,
-            _extract_responses_reasoning_text,
         )
 
         # _normalize_codex_response returns (SimpleNamespace, finish_reason_str)