fix: Use actual broker nodeID in partition metadata for Metadata responses

## Problem

Metadata responses were hardcoding partition leader and replica nodeIDs to 1,
but the actual broker's nodeID is different (0x4fd297f2 / 1329658354).

This caused Java clients to get confused:
1. Client reads: "Broker is at nodeID=0x4fd297f2"
2. Client reads: "Partition leader is nodeID=1"
3. Client looks for broker with nodeID=1 → not found
4. Client can't determine leader → retries Metadata request
5. Same wrong response → infinite retry loop until timeout

## Solution

Use the actual broker's nodeID consistently:
- LeaderID: nodeID (was int32(1))
- ReplicaNodes: [nodeID] (was [1])
- IsrNodes: [nodeID] (was [1])

Now the response is consistent:
- Broker: nodeID = 0x4fd297f2
- Partition leader: nodeID = 0x4fd297f2
- Replicas: [0x4fd297f2]
- ISR: [0x4fd297f2]

## Impact

With both fixes (hostname + nodeID):
- Schema Registry consumer won't get stuck
- Consumer can proceed to JoinGroup/SyncGroup/Fetch
- Producer can send Noop record
- Schema Registry initialization completes successfully

weed/mq/kafka/protocol/handler.go

@@ -1886,7 +1886,7 @@ func (h *Handler) handleMetadataV5ToV8(correlationID uint32, requestBody []byte,
 		for partitionID := int32(0); partitionID < partitionCount; partitionID++ {
 			binary.Write(&buf, binary.BigEndian, int16(0))    // ErrorCode
 			binary.Write(&buf, binary.BigEndian, partitionID) // PartitionIndex
-			binary.Write(&buf, binary.BigEndian, int32(1))    // LeaderID
+			binary.Write(&buf, binary.BigEndian, nodeID)    // LeaderID
 
 			// LeaderEpoch (4 bytes) - v7+ addition
 			if apiVersion >= 7 {
@@ -1895,11 +1895,11 @@ func (h *Handler) handleMetadataV5ToV8(correlationID uint32, requestBody []byte,
 
 			// ReplicaNodes array (4 bytes length + nodes)
 			binary.Write(&buf, binary.BigEndian, int32(1)) // 1 replica
-			binary.Write(&buf, binary.BigEndian, int32(1)) // NodeID 1
+			binary.Write(&buf, binary.BigEndian, nodeID) // NodeID 1
 
 			// IsrNodes array (4 bytes length + nodes)
 			binary.Write(&buf, binary.BigEndian, int32(1)) // 1 ISR node
-			binary.Write(&buf, binary.BigEndian, int32(1)) // NodeID 1
+			binary.Write(&buf, binary.BigEndian, nodeID) // NodeID 1
 
 			// OfflineReplicas array (4 bytes length + nodes) - v5+ addition
 			binary.Write(&buf, binary.BigEndian, int32(0)) // No offline replicas