Added test case for fee inputs into multiple transactions

src/test/scala/org/ergoplatform/mining/CandidateGeneratorPropSpec.scala

@@ -196,6 +196,46 @@ class CandidateGeneratorPropSpec extends ErgoCorePropertyTest {
 
   }
 
+  property("should break up fee inputs into multiple transactions if there are too many") {
+    val bh = boxesHolderGen.sample.get
+    val us = createUtxoState(bh,parameters)
+    val height = us.stateContext.currentHeight
+
+    // Generate a large number of fee boxes
+    val feeBoxes= (1 to 1000).map(_ =>
+      val value = Gen.choose(1,100).sample.get(100L, 10000L).sample.get
+      createBox(value,feeProp, creationHeight = Some(height))
+    )
+
+    // Create transactions spending these fee boxes
+    val feeTransactions = feeBoxes.map { box =>
+    val input = Input(box.id, ProverResult.empty)
+    val output = new ErgoBoxCandidate(box.value, feeProp, height)
+    new ErgoTransaction(IndexedSeq(input), IndexedSeq(output))
+
+    val txs = CandidateGenerator.collectFees(height, feeTransactions, defaultMinerPk, emptyStateContext).toSeq
+
+    // check that multiple transactions were created
+    txs.length shouldBe > (1)
+
+    // check that each transacton does not exceed a reasonable input limit
+    val maxInputsPerTx = 100 
+    txs.foreach { tx =>
+      tx.inputs.size should be <= maxInputsPerTx
+    }
+
+    // Check that all fee inputs were collected
+    val collectedInputs = txs.flatMap(_.inputs).map(_.boxId).toSet
+    val originalInputs = feeTransactions.flatMap(_.inputs).map(_.boxId).toSet
+    collectedInputs should equal(originalInputs)
+  }
+
+  // Check that all outputs go to the miner
+  txs.flatMap(_.outputs).foreach { output =>
+    output.propositionBytes shouldEqual expectedRewardOutputScriptBytes(defaultMinerPk)
+  }
+  }
+
   property("should not be able to spend recent fee boxes") {
 
     val delta          = 1