Rename AcountSession to ServerSession

Start the work of clearly distingushing client side types, server side
types and types shared over the API by renaming "AccountSession" and
"Session" names used on the server to "ServerSession".

server/database.ts

@@ -1,8 +1,13 @@
 import { readFile, unlink, writeFile } from "node:fs/promises";
 import { Schedule } from "~/shared/types/schedule";
-import { Account, Subscription, Session } from "~/shared/types/account";
+import { Account, Subscription } from "~/shared/types/account";
 import { generateDemoSchedule, generateDemoAccounts } from "./generate-demo-schedule";
 
+export interface ServerSession {
+	id: number,
+	accountId: number,
+};
+
 // For this demo I'm just storing the runtime data in JSON files. When making
 // this into proper application this should be replaced with an actual database.
 
@@ -87,9 +92,9 @@ export async function nextSessionId() {
 }
 
 export async function readSessions() {
-	return await readJson<Session[]>(sessionsPath, []);
+	return await readJson<ServerSession[]>(sessionsPath, []);
 }
 
-export async function writeSessions(sessions: Session[]) {
+export async function writeSessions(sessions: ServerSession[]) {
 	await writeFile(sessionsPath, JSON.stringify(sessions, undefined, "\t") + "\n", "utf-8");
 }