[feat] : Add dashboard slash command feature

[not-meet]

summary

Adds a UI dashboard modal to the Spam Monitor app that allows admins to view all flagged users in one place. Previously, admins could only see flagged users via the /spammonitor list slash command which returned a plain text list. This PR introduces a proper interactive modal dashboard accessible via a room action button or slash command.

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Changes Made

• implemented dashboard command thus the admin now can see the list of the flagged users in a proper UI modal
• removed /list command since the only scope of that was to let admin see flagged users in list format till a proper dashboard is not introduced
• added search bar at the top filters the list by username
• Each user entry shows: username, spam level label, total flags, and active cooldown (if any)

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Closes #13

DEMO

Screencast.from.2026-06-07.04-02-19.webm

Note -

I added format date function in this pr since without it the list of flagged users wont have proper formatted time, I am well aware the same function is introduced by me in the prev PR , once that gets merged ill update the pr with the merged format date function and languages