[Bug] Message Duplication and Out-of-Order Delivery in Multi-Bridge Setup

### Describe the bug

## Issue Description

When running `zenoh-bridge-ros2dds` on multiple machines connected to the same Zenoh router, ROS 2 messages are being duplicated extensively and delivered out of order. A single message published by a talker node results in dozens of duplicate messages received by the listener, with sequence numbers appearing in random order.

## Setup Architecture

```
Desktop (192.168.0.XXX):          Laptop (192.168.0.x):
├── Zenoh Router (port 7447)      ├── zenoh-bridge-ros2dds
├── zenoh-bridge-ros2dds          └── ROS 2 listener node
└── ROS 2 talker node
```

## Configuration Files

### Zenoh Router Config (zenoh_router_config.json5)
```json5
{
  mode: "router",
  listen: {
    endpoints: ["tcp/0.0.0.0:7447"]
  },
  scouting: {
    multicast: {
      enabled: true
    }
  }
}
```

### Bridge Config (zenoh_bridge_config.json5) - Used on both machines
```json5
{
  mode: "client",
  connect: {
    endpoints: ["tcp/127.0.0.1:7447"]  // "tcp/Desktop_IP:7447" on laptop
  },
  scouting: {
    multicast: {
      enabled: false
    },
    gossip: {
      enabled: false
    }
  },
  plugins: {
    ros2dds: {
      domain: 70,
      ros_localhost_only: false,
      reliable_routes_blocking: true,
      transient_local_cache_multiplier: 0,
    }
  }
}
```

### Docker Compose (docker-compose.yml)
```yaml
services:
  zenoh_router:
    image: eclipse/zenoh:latest
    container_name: zenoh_router
    volumes:
      - ./zenoh_router_config.json5:/zenoh/zenoh_router_config.json5:ro
    command: ["-c", "/zenoh/zenoh_router_config.json5"]
    network_mode: host

  zenoh_bridge:
    image: eclipse/zenoh-bridge-ros2dds:latest
    network_mode: host
    init: true
    stdin_open: true
    tty: true
    volumes:
      - ./zenoh_bridge_config.json5:/zenoh/zenoh_bridge_config.json5:ro
    command: ["-c", "/zenoh/zenoh_bridge_config.json5"]
    depends_on:
      - zenoh_router
```

## Problem Demonstration

### Expected Behavior
```
[INFO] [listener]: I heard: [Hello World: 1]
[INFO] [listener]: I heard: [Hello World: 2]
[INFO] [listener]: I heard: [Hello World: 3]
```

### Actual Behavior
```
[INFO] [1758189864.780930432] [listener]: I heard: [Hello World: 599]
[INFO] [1758189864.781051947] [listener]: I heard: [Hello World: 600]
[INFO] [1758189864.781274747] [listener]: I heard: [Hello World: 600]
[INFO] [1758189864.781420818] [listener]: I heard: [Hello World: 599]
[INFO] [1758189864.781503294] [listener]: I heard: [Hello World: 601]
[INFO] [1758189864.782485288] [listener]: I heard: [Hello World: 601]
[INFO] [1758189864.782609293] [listener]: I heard: [Hello World: 599]
[INFO] [1758189864.782696983] [listener]: I heard: [Hello World: 600]
[INFO] [1758189864.782779420] [listener]: I heard: [Hello World: 599]
[INFO] [1758189864.782878196] [listener]: I heard: [Hello World: 601]
```

### Topic Info Shows Multiple Publishers
```bash
$ ros2 topic info /chatter -v
Publisher count: 3

Node name: talker
Node namespace: /
Topic type: std_msgs/msg/String
Endpoint type: PUBLISHER
GID: 01.10.02.12.87.1a.46.c5.2c.86.3f.9a.00.00.15.03.00.00.00.00.00.00.00.00

Node name: zenoh_bridge_ros2dds  # Bridge 1
Node namespace: /
Topic type: std_msgs/msg/String
Endpoint type: PUBLISHER
GID: 01.10.c1.4d.02.99.e2.07.d9.c1.17.41.00.00.07.03.00.00.00.00.00.00.00.00

Node name: zenoh_bridge_ros2dds  # Bridge 2
Node namespace: /
Topic type: std_msgs/msg/String
Endpoint type: PUBLISHER
GID: 01.10.fa.3d.fa.a7.e8.7e.b0.a5.51.c4.00.00.80.03.00.00.00.00.00.00.00.00
```

## Root Cause Analysis

The issue appears to be caused by:

1. **Routing Loop**: Both bridges can discover each other over DDS (due to `ros_localhost_only: false`)
2. **Multiple Data Paths**: Messages travel through multiple routes:
   - Direct DDS between bridges
   - Via Zenoh router between bridges
3. **No Duplicate Detection**: The same message gets re-published multiple times through different paths

## Bridge Startup Logs

### Desktop Bridge
```
2025-09-18T10:16:02.552176Z  INFO main ThreadId(01) zenoh::net::runtime: Using ZID: b7c8364e1b8d5c1f1e4a5e7c8d9f2a3b
2025-09-18T10:16:02.552400Z  INFO main ThreadId(01) zenoh::api::loader: Starting required plugin "ros2dds"
2025-09-18T10:16:02.553200Z  INFO tokio-runtime-worker ThreadId(16) zenoh_plugin_ros2dds: ROS2 plugin Config { 
  domain: 70, 
  ros_localhost_only: false, 
  reliable_routes_blocking: true,
  transient_local_cache_multiplier: 0
}
```

### Laptop Bridge
```
2025-09-18T10:16:08.445123Z  INFO main ThreadId(01) zenoh::net::runtime: Using ZID: d72192711af68788a44fe79a5b2215a3
2025-09-18T10:16:08.446789Z  INFO tokio-runtime-worker ThreadId(10) zenoh_plugin_ros2dds: Discovered ROS node: talker -> ZID b7c8364e1b8d5c1f1e4a5e7c8d9f2a3b
```

## Questions

1. **Is this expected behavior** when running multiple bridges with `ros_localhost_only: false`?

2. **What is the recommended configuration** for preventing routing loops in multi-bridge setups while maintaining connectivity?

3. **Are there configuration options** to enable duplicate message detection/filtering in zenoh-bridge-ros2dds?

4. **Should different bridge instances** use different ROS domains or namespaces to prevent interference?

## Attempted Solutions

1. **Setting `ros_localhost_only: true`**: Prevents the bridge from discovering local ROS nodes
2. **Disabling multicast/gossip**: Did not resolve the duplication issue
3. **Using `reliable_routes_blocking: true`**: Did not prevent out-of-order delivery

## Expected Solution

A configuration that allows:
- Bridge on desktop to discover local ROS nodes
- Bridge on laptop to receive messages via Zenoh only
- No routing loops or message duplication
- Preserved message ordering

### To reproduce

## Steps to Reproduce

### Prerequisites
- Two Linux machines on the same network
- Docker installed on both machines
- ROS 2 Humble installed on both machines

### Step 1: Setup Desktop (192.168.0.XXX)

1. **Create configuration files**:
   ```bash
   mkdir zenoh-test && cd zenoh-test
   
   # Create router config
   cat > zenoh_router_config.json5 << EOF
   {
     mode: "router",
     listen: {
       endpoints: ["tcp/0.0.0.0:7447"]
     },
     scouting: {
       multicast: {
         enabled: true
       }
     }
   }
   EOF
   
   # Create bridge config
   cat > zenoh_bridge_config.json5 << EOF
   {
     mode: "client",
     connect: {
       endpoints: ["tcp/127.0.0.1:7447"]
     },
     scouting: {
       multicast: {
         enabled: false
       },
       gossip: {
         enabled: false
       }
     },
     plugins: {
       ros2dds: {
         domain: 70,
         ros_localhost_only: false,
         reliable_routes_blocking: true,
         transient_local_cache_multiplier: 0,
       }
     }
   }
   EOF
   ```

2. **Create docker-compose.yml**:
   ```yaml
   services:
     zenoh_router:
       image: eclipse/zenoh:latest
       container_name: zenoh_router
       volumes:
         - ./zenoh_router_config.json5:/zenoh/zenoh_router_config.json5:ro
       command: ["-c", "/zenoh/zenoh_router_config.json5"]
       network_mode: host

     zenoh_bridge:
       image: eclipse/zenoh-bridge-ros2dds:latest
       network_mode: host
       init: true
       stdin_open: true
       tty: true
       volumes:
         - ./zenoh_bridge_config.json5:/zenoh/zenoh_bridge_config.json5:ro
       command: ["-c", "/zenoh/zenoh_bridge_config.json5"]
       depends_on:
         - zenoh_router
   ```

3. **Start services**:
   ```bash
   docker compose up -d
   ```

4. **Run talker node**:
   ```bash
   export RMW_IMPLEMENTATION=rmw_cyclonedds_cpp
   export ROS_DOMAIN_ID=70
   ros2 run demo_nodes_cpp talker
   ```

### Step 2: Setup Laptop

1. **Create bridge config** (modify endpoint to point to desktop):
   ```bash
   cat > zenoh_bridge_config.json5 << EOF
   {
     mode: "client",
     connect: {
       endpoints: ["tcp/Desktop_IP:7447"]
     },
     scouting: {
       multicast: {
         enabled: false
       },
       gossip: {
         enabled: false
       }
     },
     plugins: {
       ros2dds: {
         domain: 70,
         ros_localhost_only: false,
         reliable_routes_blocking: true,
         transient_local_cache_multiplier: 0,
       }
     }
   }
   EOF
   ```

2. **Start bridge**:
   ```bash
   docker run --rm --network=host \
     -v $(pwd)/zenoh_bridge_config.json5:/zenoh/config.json5 \
     eclipse/zenoh-bridge-ros2dds:latest -c /zenoh/config.json5
   ```

3. **Run listener node**:
   ```bash
   export RMW_IMPLEMENTATION=rmw_cyclonedx_cpp
   export ROS_DOMAIN_ID=70
   ros2 run demo_nodes_cpp listener
   ```

### Step 3: Observe the Issue

1. **Check topic info**:
   ```bash
   ros2 topic info /chatter -v
   ```
   Expected: 1 publisher (talker)
   Actual: 3 publishers (talker + 2 bridge instances)

2. **Monitor listener output**:
   ```bash
   ros2 topic echo /chatter
   ```
   You will see multiple copies of each message delivered out of order.

### Expected vs Actual Results

**Expected**: Sequential message delivery with no duplicates
**Actual**: Extensive message duplication with out-of-order delivery (10+ copies per message)

### System info

- **Zenoh Version**: 1.5.1
- **zenoh-bridge-ros2dds Version**: 1.5.1
- **ROS 2 Distribution**: Humble
- **RMW Implementation**: rmw_cyclonedds_cpp
- **Operating System**: Linux (Ubuntu)
- **Network Setup**: Two machines on same LAN (192.168.0.x)

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[Bug] Message Duplication and Out-of-Order Delivery in Multi-Bridge Setup #542

Describe the bug

Issue Description

Setup Architecture

Configuration Files

Zenoh Router Config (zenoh_router_config.json5)

Bridge Config (zenoh_bridge_config.json5) - Used on both machines

Docker Compose (docker-compose.yml)

Problem Demonstration

Expected Behavior

Actual Behavior

Topic Info Shows Multiple Publishers

Root Cause Analysis

Bridge Startup Logs

Desktop Bridge

Laptop Bridge

Questions

Attempted Solutions

Expected Solution

To reproduce

Steps to Reproduce

Prerequisites

Step 1: Setup Desktop (192.168.0.XXX)

Step 2: Setup Laptop

Step 3: Observe the Issue

Expected vs Actual Results

System info

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

[Bug] Message Duplication and Out-of-Order Delivery in Multi-Bridge Setup #542

Description

Describe the bug

Issue Description

Setup Architecture

Configuration Files

Zenoh Router Config (zenoh_router_config.json5)

Bridge Config (zenoh_bridge_config.json5) - Used on both machines

Docker Compose (docker-compose.yml)

Problem Demonstration

Expected Behavior

Actual Behavior

Topic Info Shows Multiple Publishers

Root Cause Analysis

Bridge Startup Logs

Desktop Bridge

Laptop Bridge

Questions

Attempted Solutions

Expected Solution

To reproduce

Steps to Reproduce

Prerequisites

Step 1: Setup Desktop (192.168.0.XXX)

Step 2: Setup Laptop

Step 3: Observe the Issue

Expected vs Actual Results

System info

Metadata

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

Issue actions