style: clear whitespace, unused-import and blank-line lint

Strip trailing whitespace, drop unused imports/variables/global statements,
split multi-imports, fix E3xx/E1xx spacing and E712 comparisons. No behaviour
change; only E501 long lines remain in flake8.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

hbd/client/plugins/os_info.py

@@ -5,7 +5,6 @@ kernel, architecture, and distribution details.
 """
 
 import platform
-import sys
 from pathlib import Path
 from typing import Any, Dict, Optional
 
@@ -15,7 +14,7 @@ from hbd.client.plugin import InfoPlugin
 
 class OSInfoPlugin(InfoPlugin):
     """Collect operating system information.
-    
+
     This plugin gathers static OS information that rarely changes:
     - OS name and version
     - Kernel version
@@ -23,27 +22,27 @@ class OSInfoPlugin(InfoPlugin):
     - Distribution details (for Linux)
     - Python version (used by hbc)
     """
-    
+
     name = "os_info"
     version = "1.0.0"
     description = "Operating system and platform information"
     interval = 0  # InfoPlugin: collect once at startup
-    
+
     def __init__(self, config: Optional[Dict[str, Any]] = None):
         super().__init__(config)
-    
+
     async def initialize(self) -> bool:
         """Initialize the OS info plugin.
-        
+
         Returns:
             True (always succeeds - platform module is stdlib)
         """
         self.logger.info(f"Initializing {self.name} plugin")
         return True
-    
+
     async def _collect_info(self) -> Dict[str, Any]:
         """Collect OS information.
-        
+
         Returns:
             Dictionary with OS details
         """
@@ -65,15 +64,15 @@ class OSInfoPlugin(InfoPlugin):
             if self.config.get("owner"):
                 self.logger.debug(f"Adding owner from config: {self.config['owner']}")
                 data["owner"] = self.config["owner"]
-            
+
             # Add Linux-specific distribution info
             if platform.system() == "Linux":
                 data.update(self._get_linux_distro())
-            
+
             # Add macOS-specific info
             elif platform.system() == "Darwin":
                 data["macos_version"] = platform.mac_ver()[0]
-            
+
             # Add Windows-specific info
             elif platform.system() == "Windows":
                 win_ver = platform.win32_ver()
@@ -81,22 +80,22 @@ class OSInfoPlugin(InfoPlugin):
                 data["windows_version"] = win_ver[1]
                 data["windows_sp"] = win_ver[2]
                 data["windows_type"] = win_ver[3]
-            
+
             self.logger.debug(f"Collected OS info: {data['system']} {data['release']}")
             return data
-            
+
         except Exception as e:
             self.logger.error(f"Error collecting OS info: {e}", exc_info=True)
             return {}
-    
+
     def _get_linux_distro(self) -> Dict[str, str]:
         """Get Linux distribution information.
-        
+
         Returns:
             Dictionary with distribution details
         """
         distro_info = {}
-        
+
         # Try reading /etc/os-release (standard on modern Linux)
         os_release = Path("/etc/os-release")
         if os_release.exists():
@@ -121,7 +120,7 @@ class OSInfoPlugin(InfoPlugin):
                                 distro_info["distro_pretty_name"] = value
             except Exception as e:
                 self.logger.warning(f"Could not read /etc/os-release: {e}")
-        
+
         # Fallback: try lsb_release (older systems)
         elif Path("/etc/lsb-release").exists():
             try:
@@ -138,5 +137,5 @@ class OSInfoPlugin(InfoPlugin):
                                 distro_info["distro_name"] = value
             except Exception as e:
                 self.logger.warning(f"Could not read /etc/lsb-release: {e}")
-        
+
         return distro_info