Allow selecting an email, and adding it to the hash.

We don't do anything with it yet, though

src/EmailList.tsx

@@ -42,6 +42,7 @@ class EmailList extends React.Component<EmailListProps, EmailListState> {
 							emailId={e}
 							email={this.props.client!.email(e)}
 							key={e}
+							mailbox={this.props.mailbox}
 						/>
 					))}
 				</Stack>

src/EmailSummary.tsx

@@ -1,12 +1,15 @@
 import React from "react";
+import Placeholder from "react-bootstrap/Placeholder";
+
 import Client from "./client/Client";
-import { IAccount, IEmail } from "./client/types";
+import { IAccount, IEmail, IMailbox } from "./client/types";
 
 type EmailSummaryProps = {
 	account: IAccount | null;
 	client: Client | null;
 	email: IEmail | null;
 	emailId: string;
+	mailbox: IMailbox | null;
 };
 type EmailSummaryState = {};
 
@@ -28,11 +31,27 @@ class EmailSummary extends React.Component<
 	}
 
 	render() {
+		if (this.props.account == null || this.props.mailbox == null) {
+			return (
+				<div className="p-2 border pe-auto" key={this.props.emailId}>
+					<Placeholder animation="glow" />
+				</div>
+			);
+		}
+		const href =
+			"#" +
+			this.props.account.id +
+			"/" +
+			this.props.mailbox.id +
+			"/" +
+			this.props.emailId;
 		return (
 			<div className="p-2 border" key={this.props.emailId}>
+				<a className="btn" href={href}>
 					{this.props.email != null
 						? this.props.email.subject
 						: this.props.emailId}
+				</a>
 			</div>
 		);
 	}