Zabbix supply backend rebuild + data-driven model supplies

Rewrite the printer Zabbix integration (Bearer auth, host-by-IP, tag-based
supply lookup, ping) and replace the hardcoded toner table with a
modelsupplies table + CRUD + seed. Add mock Zabbix server, live test
harness, and the Playwright screenshot tooling.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tools/mock_zabbix.py

@@ -0,0 +1,144 @@
+"""Mock Zabbix 7.0 JSON-RPC server for testing the printer supply integration.
+
+Speaks just enough of the Zabbix API (api_jsonrpc.php) to exercise our
+ZabbixService end to end over real HTTP: Bearer token auth, host.get by IP,
+and item.get returning printer supply items tagged the way the real Zabbix
+templates tag them (component=supplies, type=level, color=<color>).
+
+Run standalone:
+    python tools/mock_zabbix.py --port 18080 --token testtoken
+
+Then point the app at it:
+    ZABBIX_ENABLED=true
+    ZABBIX_URL=http://localhost:18080
+    ZABBIX_TOKEN=testtoken
+
+It is also imported by tests/test_plugins/test_zabbix_live.py, which boots it
+in a background thread.
+"""
+
+import argparse
+import json
+import threading
+from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
+
+
+# one fake host, named by its IP (matches how the real shop Zabbix names hosts)
+HOSTS = {
+    '10.20.30.40': '10501',
+}
+
+# supply level items for host 10501, with Zabbix-style tags
+SUPPLY_ITEMS = {
+    '10501': [
+        {'itemid': '1', 'name': 'Black Toner Level', 'lastvalue': '4',
+         'status': '0', 'state': '0',
+         'tags': [{'tag': 'component', 'value': 'supplies'},
+                  {'tag': 'type', 'value': 'level'},
+                  {'tag': 'color', 'value': 'black'}]},
+        {'itemid': '2', 'name': 'Cyan Toner Level', 'lastvalue': '60',
+         'status': '0', 'state': '0',
+         'tags': [{'tag': 'component', 'value': 'supplies'},
+                  {'tag': 'type', 'value': 'level'},
+                  {'tag': 'color', 'value': 'cyan'}]},
+        {'itemid': '3', 'name': 'Waste Cartridge Level', 'lastvalue': '97',
+         'status': '0', 'state': '0',
+         'tags': [{'tag': 'component', 'value': 'supplies'},
+                  {'tag': 'type', 'value': 'level'}]},
+        {'itemid': '4', 'name': 'Disabled Drum Level', 'lastvalue': '0',
+         'status': '1', 'state': '0',
+         'tags': [{'tag': 'component', 'value': 'supplies'},
+                  {'tag': 'type', 'value': 'level'}]},
+    ],
+}
+
+PING_ITEMS = {
+    '10501': '1',
+}
+
+
+def build_handler(token):
+    class ZabbixHandler(BaseHTTPRequestHandler):
+        def log_message(self, *args):
+            pass  # quiet
+
+        def _send(self, payload, code=200):
+            body = json.dumps(payload).encode()
+            self.send_response(code)
+            self.send_header('Content-Type', 'application/json')
+            self.send_header('Content-Length', str(len(body)))
+            self.end_headers()
+            self.wfile.write(body)
+
+        def do_GET(self):
+            # reachability probe hits the endpoint with GET
+            self._send({'jsonrpc': '2.0', 'error': {'code': -32600}, 'id': None})
+
+        def do_POST(self):
+            length = int(self.headers.get('Content-Length', 0))
+            request = json.loads(self.rfile.read(length) or b'{}')
+            method = request.get('method')
+            params = request.get('params', {})
+            reqid = request.get('id', 1)
+
+            auth = self.headers.get('Authorization', '')
+            if auth != f'Bearer {token}':
+                self._send({'jsonrpc': '2.0',
+                            'error': {'code': -32602, 'message': 'Not authorised'},
+                            'id': reqid})
+                return
+
+            result = self._dispatch(method, params)
+            self._send({'jsonrpc': '2.0', 'result': result, 'id': reqid})
+
+        def _dispatch(self, method, params):
+            if method in ('apiinfo.version',):
+                return '7.0.0'
+            if method == 'hostgroup.get':
+                return [{'groupid': '1'}]
+            if method == 'host.get':
+                ips = (params.get('filter') or {}).get('host', [])
+                out = []
+                for ip in ips:
+                    if ip in HOSTS:
+                        out.append({'hostid': HOSTS[ip], 'host': ip, 'name': ip})
+                return out
+            if method == 'item.get':
+                hostids = params.get('hostids')
+                hostid = hostids[0] if isinstance(hostids, list) else hostids
+                search = params.get('search') or {}
+                if 'icmpping' in (search.get('key_') or ''):
+                    value = PING_ITEMS.get(hostid)
+                    return [{'lastvalue': value}] if value is not None else []
+                return SUPPLY_ITEMS.get(hostid, [])
+            return []
+
+    return ZabbixHandler
+
+
+def serve(port, token):
+    server = ThreadingHTTPServer(('127.0.0.1', port), build_handler(token))
+    return server
+
+
+def serve_in_thread(port, token):
+    """Start the mock in a daemon thread. Returns the server (call shutdown())."""
+    server = serve(port, token)
+    thread = threading.Thread(target=server.serve_forever, daemon=True)
+    thread.start()
+    return server
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description='Mock Zabbix JSON-RPC server')
+    parser.add_argument('--port', type=int, default=18080)
+    parser.add_argument('--token', default='testtoken')
+    args = parser.parse_args()
+    httpd = serve(args.port, args.token)
+    print(f"Mock Zabbix on http://127.0.0.1:{args.port}/api_jsonrpc.php "
+          f"(token: {args.token})")
+    print(f"Known host: {list(HOSTS)[0]} -> supplies + icmpping")
+    try:
+        httpd.serve_forever()
+    except KeyboardInterrupt:
+        httpd.shutdown()