Implement PBS authentication support for backup discovery

- Add PBSStorageCredential model to database schema (fingerprint now required)
- Create PBS credentials API router with CRUD operations
- Add PBS login functionality to backup service before discovery
- Create PBSCredentialsModal component for managing credentials
- Integrate PBS credentials management into ServerStoragesModal
- Update storage service to extract PBS IP and datastore info
- Add helpful hint about finding fingerprint on PBS dashboard
- Auto-accept fingerprint during login using stored credentials

src/server/database-prisma.js

@@ -361,6 +361,62 @@ class DatabaseServicePrisma {
     return grouped;
   }
 
+  // PBS Credentials CRUD operations
+  async createOrUpdatePBSCredential(credentialData) {
+    return await prisma.pBSStorageCredential.upsert({
+      where: {
+        server_id_storage_name: {
+          server_id: credentialData.server_id,
+          storage_name: credentialData.storage_name,
+        },
+      },
+      update: {
+        pbs_ip: credentialData.pbs_ip,
+        pbs_datastore: credentialData.pbs_datastore,
+        pbs_password: credentialData.pbs_password,
+        pbs_fingerprint: credentialData.pbs_fingerprint,
+        updated_at: new Date(),
+      },
+      create: {
+        server_id: credentialData.server_id,
+        storage_name: credentialData.storage_name,
+        pbs_ip: credentialData.pbs_ip,
+        pbs_datastore: credentialData.pbs_datastore,
+        pbs_password: credentialData.pbs_password,
+        pbs_fingerprint: credentialData.pbs_fingerprint,
+      },
+    });
+  }
+
+  async getPBSCredential(serverId, storageName) {
+    return await prisma.pBSStorageCredential.findUnique({
+      where: {
+        server_id_storage_name: {
+          server_id: serverId,
+          storage_name: storageName,
+        },
+      },
+    });
+  }
+
+  async getPBSCredentialsByServer(serverId) {
+    return await prisma.pBSStorageCredential.findMany({
+      where: { server_id: serverId },
+      orderBy: { storage_name: 'asc' },
+    });
+  }
+
+  async deletePBSCredential(serverId, storageName) {
+    return await prisma.pBSStorageCredential.delete({
+      where: {
+        server_id_storage_name: {
+          server_id: serverId,
+          storage_name: storageName,
+        },
+      },
+    });
+  }
+
   async close() {
     await prisma.$disconnect();
   }