fix(relay): clear clippy on integrated multi-tenant stack

The H1 fanout fix threaded a server-resolved CommunityId through the
connection registry and two membership caches, tipping three clippy lints:
register() to 8 args (too_many_arguments) and the moka cache keys to
type_complexity. Allow both locally with rationale, matching existing
repo convention (observer_owner_cache already carries the same allow in
this file; buzz-db/buzz-cli use too_many_arguments allows). Also relocate
topic_for_subscription above the req.rs test module to clear
items_after_test_module surfaced by --all-targets.

No behavior change; buzz-relay 385/0, clippy --all-targets -D warnings clean.

Co-authored-by: Tyler Longwell <tlongwell@block.xyz>
Signed-off-by: Tyler Longwell <tlongwell@block.xyz>

Author: npub1qyvc0c5kl4gqv2fd97fsk46tu378sqgy35vc83rvgfwne90sel7s0ed67d

crates/buzz-relay/src/handlers/req.rs

@@ -993,6 +993,13 @@ pub(crate) fn author_only_filters_authorized(filters: &[Filter], authed_pubkey_h
     })
 }
 
+fn topic_for_subscription(channel_id: Option<uuid::Uuid>) -> EventTopic {
+    match channel_id {
+        Some(channel_id) => EventTopic::Channel(channel_id),
+        None => EventTopic::Global,
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -1442,9 +1449,3 @@ mod tests {
     }
 }
 
-fn topic_for_subscription(channel_id: Option<uuid::Uuid>) -> EventTopic {
-    match channel_id {
-        Some(channel_id) => EventTopic::Channel(channel_id),
-        None => EventTopic::Global,
-    }
-}

crates/buzz-relay/src/state.rs

@@ -58,7 +58,11 @@ impl ConnectionManager {
     }
 
     /// Registers a connection with its outbound sender, cancellation token,
-    /// shared backpressure counter, mutable subscription map, and grace limit.
+    /// server-resolved community, shared backpressure counter, mutable
+    /// subscription map, and grace limit.
+    // Each argument is a distinct per-connection attribute stored verbatim in
+    // `ConnEntry`; a params struct would only relocate the same fields.
+    #[allow(clippy::too_many_arguments)]
     pub fn register(
         &self,
         conn_id: Uuid,
@@ -229,9 +233,11 @@ pub struct AppState {
     pub local_event_ids: Arc<moka::sync::Cache<[u8; 32], ()>>,
     /// Membership cache: (community_id, channel_id, pubkey_bytes) → is_member.
     /// Short TTL (10s) — membership changes are rare but must propagate.
+    #[allow(clippy::type_complexity)]
     pub membership_cache: Arc<moka::sync::Cache<(CommunityId, Uuid, Vec<u8>), bool>>,
     /// Accessible channel IDs cache: (community_id, pubkey_bytes) → channel UUIDs.
     /// Short TTL (10s) — invalidated on membership or channel visibility changes.
+    #[allow(clippy::type_complexity)]
     pub accessible_channels_cache: Arc<moka::sync::Cache<(CommunityId, Vec<u8>), Vec<Uuid>>>,
     /// Per-community channel visibility string, used to gate the private-channel fan-out
     /// access check so open channels stay zero-cost. Invalidated on a flip.