fix(lastleg): read committed order command replays after lock waits

scripts/admin-test-env-modules/phase4-tail-order-controls-contract.test.mjs

@@ -178,6 +178,12 @@ test('fresh immutable IDs drive two full cycles and preserve independent HOLD ac
   await verifyReceivedOrderHold(context)
   const proof=context.createdResources.phase4TailOrderControls.holdInventoryProof
   assert.equal(proof.status,'VERIFIED');assert.equal(proof.restored,true);assert.equal(order.version,8)
+  assert.equal(proof.concurrentCommands.length,2)
+  for(const command of proof.concurrentCommands) {
+    assert.equal(command.copies,2)
+    assert.deepEqual(command.replies[0],command.replies[1])
+    assert.equal(command.replies[0].version,command.expectedVersion+1)
+  }
   assert.equal(proof.snapshots.C2_RELEASED.positions.find(row=>row.id==='22').holdPackages,1)
   assert.equal(proof.snapshots.AFTER.balances[0].availablePackages,4)
   assert.equal(calls.filter(c=>c.path.endsWith('/manual')).length,2)
@@ -185,6 +191,41 @@ test('fresh immutable IDs drive two full cycles and preserve independent HOLD ac
   assert.equal(calls.filter(c=>c.method==='POST'&&c.path.endsWith('/inventory/release')).length,1)
 })
 
+test('hold duplicate requests are in flight together, with bounded concurrency of two',async()=>{
+  const {context}=holdModel()
+  const originalRequest=context.request
+  let active=0,peak=0
+  context.request=async(method,path,...args)=>{
+    if(method!=='PUT'||!path.includes('/orders/')) return originalRequest(method,path,...args)
+    active++;peak=Math.max(peak,active)
+    try { await new Promise(resolve=>setImmediate(resolve));return await originalRequest(method,path,...args) }
+    finally {active--}
+  }
+  await verifyReceivedOrderHold(context)
+  assert.equal(peak,2)
+  assert.equal(active,0)
+})
+
+test('ambiguous parallel hold waits for its sibling and never starts recovery writes',async()=>{
+  const {context,calls}=holdModel()
+  const originalRequest=context.request
+  let holdRequests=0,siblingSettled=false
+  context.request=async(method,path,body,...args)=>{
+    if(method==='PUT' && body?.held && ++holdRequests<=2) {
+      if(holdRequests===1) throw new Error('lost response')
+      await new Promise(resolve=>setImmediate(resolve))
+      const response=await originalRequest(method,path,body,...args)
+      siblingSettled=true
+      return response
+    }
+    return originalRequest(method,path,body,...args)
+  }
+  await assert.rejects(verifyReceivedOrderHold(context),/lost response/)
+  assert.equal(siblingSettled,true)
+  assert.equal(context.createdResources.phase4TailOrderControls.holdInventoryProof.uncertainWrite,true)
+  assert.ok(!calls.some(call=>call.path.endsWith('/inventory/release')||call.body?.held===false))
+})
+
 for(const fault of ['stale marker','no evidence','wrong immutable customer','missing position','unsafe bucket','not enough stock','moved source']) {
   test(`missing or unsafe fresh hold prerequisite blocks all writes: ${fault}`,async()=>{
     const {context,calls}=holdModel(fault)