OperServ: IGNORE — silence a user across all services

IGNORE ADD [+expiry] <mask> [reason] / DEL <mask> / LIST. While a user
matches, the dispatch choke-point drops their service commands silently.
A mask with an @ matches nick!*@host (ident isn't tracked); a bare mask
matches the nick; matching is case-insensitive with lazy expiry. Admin-
only, and an operator is never ignored (so staff can't lock themselves
out). Node-local and in-memory, like the auth and request throttles — a
fast transient moderation tool, not persisted or federated.

api/src/lib.rs

@@ -449,6 +449,14 @@ pub struct AkillView {
     pub expires: Option<u64>,
 }
 
+// A services ignore held by OperServ.
+#[derive(Debug, Clone)]
+pub struct IgnoreView {
+    pub mask: String,
+    pub reason: String,
+    pub expires: Option<u64>,
+}
+
 #[derive(Debug, Clone)]
 pub struct BotView {
     pub nick: String,
@@ -701,6 +709,10 @@ pub trait Store {
     fn akill_add(&mut self, kind: &str, mask: &str, setter: &str, reason: &str, expires: Option<u64>) -> Result<bool, RegError>;
     fn akill_del(&mut self, kind: &str, mask: &str) -> Result<bool, RegError>;
     fn akills(&self) -> Vec<AkillView>;
+    // Services ignores (node-local, oper-only).
+    fn ignore_add(&mut self, mask: &str, reason: &str, expires: Option<u64>);
+    fn ignore_del(&mut self, mask: &str) -> bool;
+    fn ignores(&self) -> Vec<IgnoreView>;
     fn register_channel(&mut self, name: &str, founder: &str) -> Result<(), ChanError>;
     fn drop_channel(&mut self, name: &str) -> Result<(), ChanError>;
     fn set_mlock(&mut self, name: &str, on: &str, off: &str) -> Result<(), ChanError>;