Feat/587-circuit-relay (#611)

* feat: implemented setup of circuit relay and test cases

* chore: remove test files to be rewritten

* added 1 test suite for protocol

* added 1 test suite for discovery

* fixed protocol timeouts and message types to handle reservations and stream operations.

* Resolved merge conflict in libp2p/tools/utils.py by combining timeout approach with retry mechanism

* fix: linting issues

* docs: updated documentation with circuit-relay

* chore: added enums, improved typing, security and examples

* fix: created proper __init__ file to ensure importability

* fix: replace transport_opt with listen_addrs in examples, fixed typing and improved code

* fix type checking issues across relay module and test suite

* regenerated circuit_pb2 file protobuf version 3

* fixed circuit relay example and moved imports to top in test_security_multistream

* chore: moved imports to the top

* chore: fixed linting of test_circuit_v2_transport.py

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Co-authored-by: Manu Sheel Gupta <manusheel.edu@gmail.com>

libp2p/tools/utils.py

@@ -87,14 +87,16 @@ async def connect(node1: IHost, node2: IHost) -> None:
     addr = node2.get_addrs()[0]
     info = info_from_p2p_addr(addr)
 
-    # Add retry logic for more robust connection
+    # Add retry logic for more robust connection with timeout
     max_retries = 3
     retry_delay = 0.2
     last_error = None
 
     for attempt in range(max_retries):
         try:
-            await node1.connect(info)
+            # Use timeout for each connection attempt
+            with trio.move_on_after(5):  # 5 second timeout
+                await node1.connect(info)
 
             # Verify connection is established in both directions
             if (