[frontend/pages] Add links between login and register pages

Iceshrimp.Frontend/Pages/Login.razor

@@ -27,6 +27,7 @@
                required="required"
                @bind="@Password"/>
         <button class="button" @onclick="Submit" disabled="@Loading">@Loc["Login"]</button>
+        <a class="register-link" href="/register">@Loc["Register a new account"]</a>
     </div>
 
     @if (Loading)

Iceshrimp.Frontend/Pages/Login.razor.css

@@ -100,3 +100,7 @@
     transition: border-color 250ms;
     border-color: var(--notice-color);
 }
+
+.register-link {
+    margin-top: 2rem;
+}

Iceshrimp.Frontend/Pages/Register.razor

@@ -45,6 +45,7 @@
         {
             <div>@Loc["Registrations for this instance are closed."]</div>
         }
+        <a class="login-link" href="/login">@Loc["Login to an existing account"]</a>
     </div>
 }
 

Iceshrimp.Frontend/Pages/Register.razor.css

@@ -18,3 +18,7 @@ input:invalid {
 .logo {
     height: 3rem;
 }
+
+.login-link {
+    margin-top: 2rem;
+}