Adds new tile on the admin home page with system data. (#301)

* Adds new tile on the admin home page with system data. Also fixes the active users bug in the pie chart

* Fixes missing parentheses

* Updates user stats cache when signing in

* Reads active number of users from session provider

* Removes unused variable

* Small improvements

* Removes acl properties from system data websocket and performs initial push of data

* fix: remove acl fetch

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Co-authored-by: DecDuck <declanahofmeyr@gmail.com>

server/internal/session/cache.ts

@@ -23,6 +23,11 @@ export default function createCacheSessionProvider() {
       const session = await sessions.get(token);
       return session ? (session as T) : undefined; // Ensure undefined is returned if session is not found
     },
+    async getNumberActiveSessions() {
+      const now = new Date();
+      const allSessions = await sessions.getItems(await sessions.getKeys());
+      return allSessions.filter(({ value }) => value.expiresAt > now).length;
+    },
     async updateSession(token, data) {
       return (await this.setSession(token, data)) !== undefined;
     },