mempool: snapshot 5 + query: new tools + server: endpoints

crates/brk_mempool/src/block_builder/tx_node.rs

@@ -0,0 +1,63 @@
+use brk_types::{Sats, VSize};
+use smallvec::SmallVec;
+
+use crate::types::{PoolIndex, TxIndex};
+
+/// A transaction node in the dependency graph.
+///
+/// Created fresh for each block building cycle, then discarded.
+pub struct TxNode {
+    /// Index into mempool entries (for final output)
+    pub tx_index: TxIndex,
+
+    /// Index in the graph pool
+    pub pool_index: PoolIndex,
+
+    /// Transaction fee
+    pub fee: Sats,
+
+    /// Transaction virtual size
+    pub vsize: VSize,
+
+    /// Parent transactions (dependencies)
+    pub parents: SmallVec<[PoolIndex; 4]>,
+
+    /// Child transactions (dependents)
+    pub children: SmallVec<[PoolIndex; 8]>,
+
+    /// Cumulative fee (self + all ancestors)
+    pub ancestor_fee: Sats,
+
+    /// Cumulative vsize (self + all ancestors)
+    pub ancestor_vsize: VSize,
+
+    /// Whether this tx has been selected
+    pub selected: bool,
+
+    /// Generation counter for heap staleness detection
+    pub generation: u32,
+}
+
+impl TxNode {
+    pub fn new(
+        tx_index: TxIndex,
+        pool_index: PoolIndex,
+        fee: Sats,
+        vsize: VSize,
+        ancestor_fee: Sats,
+        ancestor_vsize: VSize,
+    ) -> Self {
+        Self {
+            tx_index,
+            pool_index,
+            fee,
+            vsize,
+            parents: SmallVec::new(),
+            children: SmallVec::new(),
+            ancestor_fee,
+            ancestor_vsize,
+            selected: false,
+            generation: 0,
+        }
+    }
+}