[frontend] Add Instance Metadata service

Iceshrimp.Frontend/Core/ControllerModels/InstanceControllerModel.cs

@@ -0,0 +1,10 @@
+using Iceshrimp.Frontend.Core.Services;
+using Iceshrimp.Shared.Schemas.Web;
+
+namespace Iceshrimp.Frontend.Core.ControllerModels;
+
+internal class InstanceControllerModel(ApiClient api)
+{
+    public Task<InstanceResponse> GetInstance() =>
+        api.CallAsync<InstanceResponse>(HttpMethod.Get, "/instance");
+}

Iceshrimp.Frontend/Core/Services/ApiService.cs

@@ -8,6 +8,7 @@ internal class ApiService(ApiClient client)
 	public readonly AuthControllerModel          Auth           = new(client);
 	public readonly DriveControllerModel         Drive          = new(client);
 	public readonly EmojiControllerModel         Emoji          = new(client);
+	public readonly InstanceControllerModel      Instance       = new(client);
 	public readonly NoteControllerModel          Notes          = new(client);
 	public readonly NotificationControllerModel  Notifications  = new(client);
 	public readonly SearchControllerModel        Search         = new(client);

Iceshrimp.Frontend/Core/Services/MetadataService.cs

@@ -0,0 +1,16 @@
+using Iceshrimp.Shared.Schemas.Web;
+using Microsoft.AspNetCore.Components;
+
+namespace Iceshrimp.Frontend.Core.Services;
+
+internal class MetadataService
+{
+    [Inject] private ApiService                   Api      { get; set; }
+    public           Lazy<Task<InstanceResponse>> Instance { get; set; }
+
+    public MetadataService(ApiService api)
+    {
+        Api      = api;
+        Instance = new Lazy<Task<InstanceResponse>>(() => Api.Instance.GetInstance());
+    }
+}

Iceshrimp.Frontend/Startup.cs

@@ -25,6 +25,7 @@ builder.Services.AddScoped<AuthenticationStateProvider, CustomAuthStateProvider>
 builder.Services.AddSingleton<ComposeService>();
 builder.Services.AddSingleton<StateService>();
 builder.Services.AddSingleton<EmojiService>();
+builder.Services.AddSingleton<MetadataService>();
 builder.Services.AddSingleton<VersionService>();
 builder.Services.AddSingleton<MessageService>();
 builder.Services.AddSingleton<GlobalComponentSvc>();