drop TxBatcher interface

overlay/batch/batch.go

@@ -1,7 +1,5 @@
 package batch
 
-import "net/netip"
-
 type RxBatcher interface {
 	// Commit commits pkt to be flushed by the batch. The caller must keep pkt valid until the next Flush, and not re-use it.
 	Commit(pkt []byte) error
@@ -9,21 +7,8 @@ type RxBatcher interface {
 	// a flow's payload-bearing packets are never reordered relative to each
 	// other. Cross-flow and cross-lane order is not preserved, and two shapes
 	// may legally be overtaken by later same-flow data: pure ACKs (by design,
-	// stale ACKs are ignored) and unparseable shapes such as fragments (an
-	// accepted tradeoff; see MultiCoalescer).
+	// stale ACKs are ignored) and unparseable shapes such as fragments (an accepted tradeoff; see MultiCoalescer).
 	// Returns the first error observed; keeps draining so one bad packet doesn't hold up the rest.
 	// After Flush returns, committed payload slices may be recycled.
 	Flush() error
 }
-
-type TxBatcher interface {
-	// Reserve creates a pkt to borrow
-	Reserve(sz int) []byte
-	// Commit borrows pkt and records its destination. The caller must
-	// keep pkt valid until the next Flush.
-	Commit(pkt []byte, dst netip.AddrPort)
-	// Flush emits every queued packet via the underlying batch writer in arrival order and reports how many were
-	// actually written. A short count means some destinations were undeliverable, not that the batch failed.
-	// After Flush returns, borrowed payload slices may be recycled.
-	Flush() (int, error)
-}