Replace custom socket implementation with SignalR.

Replace MSAL and custom cookie auth with Microsoft.Identity.EntityFramework
Also some UI redesign to accommodate different login experience.

Shogi.UI/Layout/MainLayout.razor

@@ -0,0 +1,7 @@
+@inherits LayoutComponentBase
+
+<div class="MainLayout PrimaryTheme">
+	<NavMenu />
+	@Body
+</div>
+

Shogi.UI/Layout/MainLayout.razor.css

@@ -0,0 +1,5 @@
+.MainLayout {
+	display: grid;
+	grid-template-columns: auto 1fr;
+	place-items: stretch;
+}

Shogi.UI/Layout/NavMenu.razor

@@ -0,0 +1,52 @@
+@inject NavigationManager navigator
+@inject ShogiApi Api
+
+<div class="NavMenu PrimaryTheme ThemeVariant--Contrast">
+	<h1>Shogi</h1>
+	<p>
+		<a href="/">Home</a>
+	</p>
+
+	<AuthorizeView>
+		<p>
+			<a href="/search">Search</a>
+		</p>
+
+		<p>
+			<button class="href" @onclick="CreateSession">Create</button>
+		</p>
+	</AuthorizeView>
+
+	<div class="spacer" />
+
+	<AuthorizeView>
+		<Authorized>
+			<p>@context.User.Identity?.Name</p>
+			<p>
+				<a href="logout">Logout</a>
+			</p>
+		</Authorized>
+		<NotAuthorized>
+			<p>
+				<a href="login">Login</a>
+			</p>
+			<p>
+				<a href="register">Register</a>
+			</p>
+		</NotAuthorized>
+	</AuthorizeView>
+</div>
+
+
+@code {
+
+	async Task CreateSession()
+	{
+		var sessionId = await Api.PostSession();
+		if (!string.IsNullOrEmpty(sessionId))
+		{
+			navigator.NavigateTo($"/play/{sessionId}");
+		}
+	}
+
+}

Shogi.UI/Layout/NavMenu.razor.css

@@ -0,0 +1,15 @@
+.NavMenu {
+	display: flex;
+	flex-direction: column;
+	border-right: 2px solid #444;
+}
+
+.NavMenu > * {
+	padding: 0 0.5rem;
+}
+.NavMenu h1 {
+}
+
+.NavMenu .spacer {
+	flex: 1;
+}