fix: Channel creation matching bug

Bug where the channel creation dialog wouldn't throw an error if you
typed the name of an existing channel that had hyphens, or a channel
with the same name but spaces instead of hyphens. This is because
channelnames are stores with underscores internally, and channelnames
were not sanitized in the `checkChannel()` method on the `Db` class

src/lib/server/db/index.ts

@@ -73,6 +73,7 @@ class Db {
 
   async checkChannel(channel: string): Promise<boolean> {
     try {
+      channel = sanitizeChannelName(channel);
       const res = await this.client.execute(`SELECT table_name FROM system_schema.tables WHERE keyspace_name = 'channels' AND table_name = ?`, [
         channel.toLowerCase(),
       ]);