fix: resolve 23 ruff lint errors

Fixes #1149

tests/unit/test_hermes_monitor.py

@@ -7,7 +7,6 @@ Refs: #1073
 """
 
 import json
-from io import BytesIO
 from unittest.mock import MagicMock, patch
 
 import pytest
@@ -79,7 +78,9 @@ def test_get_memory_info_handles_subprocess_failure(monitor):
 
 @pytest.mark.asyncio
 async def test_check_memory_ok(monitor):
-    with patch.object(monitor, "_get_memory_info", return_value={"free_gb": 20.0, "total_gb": 64.0}):
+    with patch.object(
+        monitor, "_get_memory_info", return_value={"free_gb": 20.0, "total_gb": 64.0}
+    ):
         result = await monitor._check_memory()
 
     assert result.name == "memory"
@@ -126,7 +127,7 @@ async def test_check_memory_exception_returns_unknown(monitor):
 @pytest.mark.asyncio
 async def test_check_disk_ok(monitor):
     usage = MagicMock()
-    usage.free = 100 * (1024**3)   # 100 GB
+    usage.free = 100 * (1024**3)  # 100 GB
     usage.total = 500 * (1024**3)  # 500 GB
     usage.used = 400 * (1024**3)
 
@@ -140,7 +141,7 @@ async def test_check_disk_ok(monitor):
 @pytest.mark.asyncio
 async def test_check_disk_low_triggers_cleanup(monitor):
     usage = MagicMock()
-    usage.free = 5 * (1024**3)    # 5 GB — below threshold
+    usage.free = 5 * (1024**3)  # 5 GB — below threshold
     usage.total = 500 * (1024**3)
     usage.used = 495 * (1024**3)
 
@@ -176,12 +177,8 @@ async def test_check_disk_critical_when_cleanup_fails(monitor):
 
 
 def test_get_ollama_status_reachable(monitor):
-    tags_body = json.dumps({
-        "models": [{"name": "qwen3:30b"}, {"name": "llama3.1:8b"}]
-    }).encode()
-    ps_body = json.dumps({
-        "models": [{"name": "qwen3:30b", "size": 1000}]
-    }).encode()
+    tags_body = json.dumps({"models": [{"name": "qwen3:30b"}, {"name": "llama3.1:8b"}]}).encode()
+    ps_body = json.dumps({"models": [{"name": "qwen3:30b", "size": 1000}]}).encode()
 
     responses = [
         _FakeHTTPResponse(tags_body),