Add interoperability test for py-libp2p and js-libp2p with enhanced logging

tests/interop/js_libp2p/README.md

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+# py-libp2p and js-libp2p Interoperability Tests
+
+This repository contains interoperability tests for py-libp2p and js-libp2p using the /ipfs/ping/1.0.0 protocol. The goal is to verify compatibility in stream multiplexing, protocol negotiation, ping handling, transport layer, and multiaddr parsing.
+
+## Directory Structure
+
+- js_node/ping.js: JavaScript implementation of a ping server and client using libp2p.
+- py_node/ping.py: Python implementation of a ping server and client using py-libp2p.
+- scripts/run_test.sh: Shell script to automate running the server and client for testing.
+- README.md: This file.
+
+## Prerequisites
+
+- Python 3.8+ with `py-libp2p` and dependencies (`pip install libp2p trio cryptography multiaddr`).
+- Node.js 16+ with `libp2p` dependencies (`npm install @libp2p/core @libp2p/tcp @chainsafe/libp2p-noise @chainsafe/libp2p-yamux @libp2p/ping @libp2p/identify @multiformats/multiaddr`).
+- Bash shell for running `run_test.sh`.
+
+## Running Tests
+
+1. Change directory:
+
+```
+cd tests/interop/js_libp2p
+```
+
+2. Install dependencies:
+
+```
+For JavaScript: cd js_node && npm install && cd ...
+```
+
+3. Run the automated test:
+
+For Linux and Mac users:
+
+```
+chmod +x scripts/run_test.sh
+./scripts/run_test.sh
+```
+
+For Windows users:
+
+```
+.\scripts\run_test.ps1
+```
+
+This starts the Python server on port 8000 and runs the JavaScript client to send 5 pings.
+
+## Debugging
+
+- Logs are saved in py_node/py_server.log and js_node/js_client.log.
+- Check for:
+  - Successful connection establishment.
+  - Protocol negotiation (/ipfs/ping/1.0.0).
+  - 32-byte payload echo in server logs.
+  - RTT and payload hex in client logs.
+
+## Test Plan
+
+### The test verifies:
+
+- Stream Multiplexer Compatibility: Yamux is used and negotiates correctly.
+- Multistream Protocol Negotiation: /ipfs/ping/1.0.0 is selected via multistream-select.
+- Ping Protocol Handler: Handles 32-byte payloads per the libp2p ping spec.
+- Transport Layer Support: TCP is used; WebSocket support is optional.
+- Multiaddr Parsing: Correctly resolves multiaddr strings.
+- Logging: Includes peer ID, RTT, and payload hex for debugging.
+
+## Current Status
+
+### Working:
+
+- TCP transport and Noise encryption are functional.
+- Yamux multiplexing is implemented in both nodes.
+- Multiaddr parsing works correctly.
+- Logging provides detailed debug information.
+
+## Not Working:
+
+- Ping protocol handler fails to complete pings (JS client reports "operation aborted").
+- Potential issues with stream handling or protocol negotiation.