feat: improve coordinator peer mapping performance (#23696)

- Skipping DB querying entirely for peers that aren't actually connected
to our coordinator
- Opportunistically batching the queries for peers

coderd/database/queries/tailnet.sql

@@ -96,28 +96,6 @@ DELETE
 FROM tailnet_tunnels
 WHERE coordinator_id = $1 and src_id = $2;
 
--- name: GetTailnetTunnelPeerIDs :many
-SELECT dst_id as peer_id, coordinator_id, updated_at
-FROM tailnet_tunnels
-WHERE tailnet_tunnels.src_id = $1
-UNION
-SELECT src_id as peer_id, coordinator_id, updated_at
-FROM tailnet_tunnels
-WHERE tailnet_tunnels.dst_id = $1;
-
--- name: GetTailnetTunnelPeerBindings :many
-SELECT id AS peer_id, coordinator_id, updated_at, node, status
-FROM tailnet_peers
-WHERE id IN (
-  SELECT dst_id as peer_id
-  FROM tailnet_tunnels
-  WHERE tailnet_tunnels.src_id = $1
-  UNION
-  SELECT src_id as peer_id
-  FROM tailnet_tunnels
-  WHERE tailnet_tunnels.dst_id = $1
-);
-
 -- For PG Coordinator HTMLDebug
 
 -- name: GetAllTailnetCoordinators :many
@@ -128,3 +106,22 @@ SELECT * FROM tailnet_peers;
 
 -- name: GetAllTailnetTunnels :many
 SELECT * FROM tailnet_tunnels;
+
+-- name: GetTailnetTunnelPeerIDsBatch :many
+SELECT src_id AS lookup_id, dst_id AS peer_id, coordinator_id, updated_at
+FROM tailnet_tunnels WHERE src_id = ANY(@ids :: uuid[])
+UNION ALL
+SELECT dst_id AS lookup_id, src_id AS peer_id, coordinator_id, updated_at
+FROM tailnet_tunnels WHERE dst_id = ANY(@ids :: uuid[]);
+
+-- name: GetTailnetTunnelPeerBindingsBatch :many
+SELECT tp.id AS peer_id, tp.coordinator_id, tp.updated_at, tp.node, tp.status,
+       tunnels.lookup_id
+FROM (
+  SELECT dst_id AS peer_id, src_id AS lookup_id
+  FROM tailnet_tunnels WHERE src_id = ANY(@ids :: uuid[])
+  UNION
+  SELECT src_id AS peer_id, dst_id AS lookup_id
+  FROM tailnet_tunnels WHERE dst_id = ANY(@ids :: uuid[])
+) tunnels
+INNER JOIN tailnet_peers tp ON tp.id = tunnels.peer_id;