Split InfoServ into one file per command

POST/DEL/LIST each move to their own file (each still parameterised by
bulletin kind, so OPOST/ODEL/OLIST route to the same handler); the kind
constants stay in lib.rs beside the dispatcher. No behaviour change.

modules/infoserv/src/del.rs

@@ -0,0 +1,21 @@
+use fedserv_api::{Priv, Sender, ServiceCtx, Store};
+
+// DEL/ODEL <number>: remove a bulletin by its listed position. Admin only.
+pub fn handle(me: &str, from: &Sender, kind: &str, num: Option<&str>, ctx: &mut ServiceCtx, db: &mut dyn Store) {
+    if !from.privs.has(Priv::Admin) {
+        ctx.notice(me, from.uid, "Access denied — that command is for services operators.");
+        return;
+    }
+    let which = if kind == super::OPER { "oper" } else { "public" };
+    let Some(n) = num.and_then(|n| n.parse::<usize>().ok()) else {
+        ctx.notice(me, from.uid, format!("Syntax: {} <number>", if kind == super::OPER { "ODEL" } else { "DEL" }));
+        return;
+    };
+    match db.news(kind).get(n.wrapping_sub(1)) {
+        Some(item) if n >= 1 => {
+            db.news_del(item.id);
+            ctx.notice(me, from.uid, format!("Removed \x02{which}\x02 bulletin \x02{n}\x02."));
+        }
+        _ => ctx.notice(me, from.uid, format!("There's no \x02{which}\x02 bulletin \x02{n}\x02.")),
+    }
+}