Implement ban guarding. Some ip fixes

internal/database/seed.sql

@@ -42,7 +42,7 @@ CREATE TABLE IF NOT EXISTS admins (
 
 CREATE TABLE IF NOT EXISTS bans (
     id INTEGER PRIMARY KEY AUTOINCREMENT,
-    ip_hash TEXT NOT NULL,
+    ip_hash TEXT NOT NULL UNIQUE,
     reason TEXT NOT NULL,
     expiration DATETIME NOT NULL 
 );