feat: initial category permissions and rework of category crud routes

crates/core/config/Revolt.toml

@@ -200,6 +200,7 @@ message_reactions = 20
 server_emoji = 100
 server_roles = 200
 server_channels = 200
+server_categories = 50
 
 # How many hours since creation a user is considered new
 new_user_hours = 72

crates/core/config/src/lib.rs

@@ -281,6 +281,7 @@ pub struct GlobalLimits {
     pub server_emoji: usize,
     pub server_roles: usize,
     pub server_channels: usize,
+    pub server_categories: usize,
 
     pub new_user_hours: usize,