feat(daemon): Add UPSD (NUT) protocol support, Proxmox VM shutdown action, pause/resume monitoring, and network-loss/unreachable handling; bump config version to 4.2

ts/protocol/resolver.ts

@@ -0,0 +1,49 @@
+/**
+ * ProtocolResolver - Routes UPS status queries to the correct protocol implementation
+ *
+ * Abstracts away SNMP vs UPSD differences so the daemon is protocol-agnostic.
+ * Both protocols return the same IUpsStatus interface from ts/snmp/types.ts.
+ */
+
+import type { NupstSnmp } from '../snmp/manager.ts';
+import type { NupstUpsd } from '../upsd/client.ts';
+import type { ISnmpConfig, IUpsStatus } from '../snmp/types.ts';
+import type { IUpsdConfig } from '../upsd/types.ts';
+import type { TProtocol } from './types.ts';
+
+export class ProtocolResolver {
+  private snmp: NupstSnmp;
+  private upsd: NupstUpsd;
+
+  constructor(snmp: NupstSnmp, upsd: NupstUpsd) {
+    this.snmp = snmp;
+    this.upsd = upsd;
+  }
+
+  /**
+   * Get UPS status using the specified protocol
+   * @param protocol Protocol to use ('snmp' or 'upsd')
+   * @param snmpConfig SNMP configuration (required for 'snmp' protocol)
+   * @param upsdConfig UPSD configuration (required for 'upsd' protocol)
+   * @returns UPS status
+   */
+  public getUpsStatus(
+    protocol: TProtocol,
+    snmpConfig?: ISnmpConfig,
+    upsdConfig?: IUpsdConfig,
+  ): Promise<IUpsStatus> {
+    switch (protocol) {
+      case 'upsd':
+        if (!upsdConfig) {
+          throw new Error('UPSD configuration required for UPSD protocol');
+        }
+        return this.upsd.getUpsStatus(upsdConfig);
+      case 'snmp':
+      default:
+        if (!snmpConfig) {
+          throw new Error('SNMP configuration required for SNMP protocol');
+        }
+        return this.snmp.getUpsStatus(snmpConfig);
+    }
+  }
+}