Add system settings, audit logging, user management, and dark mode fixes

System Settings:
- Add SystemSettings.vue with Zabbix integration, SMTP/email config, SAML SSO settings
- Add Setting model with key-value storage and typed values
- Add settings API with caching

Audit Logging:
- Add AuditLog model tracking user, IP, action, entity changes
- Add comprehensive audit logging to all CRUD operations:
  - Machines, Computers, Equipment, Network devices, VLANs, Subnets
  - Printers, USB devices (including checkout/checkin)
  - Applications, Settings, Users/Roles
- Track old/new values for all field changes
- Mask sensitive values (passwords, tokens) in logs

User Management:
- Add UsersList.vue with full user CRUD
- Add Role management with granular permissions
- Add 41 predefined permissions across 10 categories
- Add users API with roles and permissions endpoints

Reports:
- Add TonerReport.vue for printer supply monitoring

Dark Mode Fixes:
- Fix map position section in PCForm, PrinterForm
- Fix alert-warning in KnowledgeBaseDetail
- All components now use CSS variables for theming

CLI Commands:
- Add flask seed permissions
- Add flask seed settings

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

plugins/printers/services/zabbix_service.py

@@ -6,6 +6,8 @@ from typing import Dict, List, Optional
 import requests
 from flask import current_app
 
+from shopdb.extensions import cache
+
 logger = logging.getLogger(__name__)
 
 
@@ -14,20 +16,70 @@ class ZabbixService:
     Zabbix API service for real-time printer supply lookups.
 
     Queries Zabbix by IP address to get current supply levels.
-    No caching - always returns live data.
+    Use getsuppliesbyip_cached() for cached lookups or
+    getsuppliesbyip() for live data.
+
+    Configuration:
+        ZABBIX_ENABLED: Set to True to enable Zabbix integration (default: False)
+        ZABBIX_URL: Zabbix API URL (e.g., http://zabbix.example.com:8080)
+        ZABBIX_TOKEN: Zabbix API authentication token
     """
 
+    CACHE_TTL = 600  # 10 minutes
+    REACHABLE_CHECK_TTL = 60  # Check reachability every 60 seconds
+
     def __init__(self):
         self._url = None
         self._token = None
+        self._enabled = None
+
+    @property
+    def isenabled(self) -> bool:
+        """Check if Zabbix integration is enabled."""
+        # Check database setting first, fall back to env var
+        from shopdb.core.models import Setting
+        db_enabled = Setting.get('zabbix_enabled')
+        if db_enabled is not None:
+            return bool(db_enabled)
+        # Fall back to env var for backwards compatibility
+        return current_app.config.get('ZABBIX_ENABLED', False)
 
     @property
     def isconfigured(self) -> bool:
-        """Check if Zabbix is configured."""
-        self._url = current_app.config.get('ZABBIX_URL')
-        self._token = current_app.config.get('ZABBIX_TOKEN')
+        """Check if Zabbix is enabled and configured."""
+        if not self.isenabled:
+            return False
+        # Check database settings first, fall back to env vars
+        from shopdb.core.models import Setting
+        self._url = Setting.get('zabbix_url') or current_app.config.get('ZABBIX_URL')
+        self._token = Setting.get('zabbix_token') or current_app.config.get('ZABBIX_TOKEN')
         return bool(self._url and self._token)
 
+    @property
+    def isreachable(self) -> bool:
+        """Check if Zabbix is reachable (cached for 60 seconds)."""
+        if not self.isenabled or not self.isconfigured:
+            return False
+
+        cache_key = 'zabbix_reachable'
+        cached = cache.get(cache_key)
+        if cached is not None:
+            return cached
+
+        # Quick connectivity check with 500ms timeout
+        try:
+            response = requests.get(
+                f"{self._url}/api_jsonrpc.php",
+                timeout=0.5
+            )
+            reachable = response.status_code in (200, 401, 403, 405)
+        except requests.RequestException:
+            reachable = False
+
+        cache.set(cache_key, reachable, timeout=self.REACHABLE_CHECK_TTL)
+        logger.debug(f"Zabbix reachability check: {reachable}")
+        return reachable
+
     def _apicall(self, method: str, params: Dict) -> Optional[Dict]:
         """Make a Zabbix API call."""
         if not self.isconfigured:
@@ -46,7 +98,7 @@ class ZabbixService:
                 f"{self._url}/api_jsonrpc.php",
                 json=payload,
                 headers={'Content-Type': 'application/json'},
-                timeout=10
+                timeout=0.5  # 500ms timeout - fail fast if Zabbix is slow/unreachable
             )
             response.raise_for_status()
             data = response.json()
@@ -131,3 +183,21 @@ class ZabbixService:
         """Get Zabbix host ID for an IP address."""
         host = self.gethostbyip(ip)
         return host['hostid'] if host else None
+
+    def getsuppliesbyip_cached(self, ip: str) -> Optional[List[Dict]]:
+        """Get printer supply levels with caching (10-minute TTL)."""
+        cache_key = f'zabbix_supplies_{ip}'
+        result = cache.get(cache_key)
+        if result is not None:
+            return result
+
+        result = self.getsuppliesbyip(ip)
+        if result is not None:
+            cache.set(cache_key, result, timeout=self.CACHE_TTL)
+        return result
+
+    def clearcache(self, ip: str = None):
+        """Clear cached supply data for one IP or all."""
+        if ip:
+            cache.delete(f'zabbix_supplies_{ip}')
+        cache.delete('printers_low_supplies')