feat(client): implement an engineio client based on Stream + Sink

[Totodore]

TODO

• Error cases and ergonomics
• Heartbeat timeouts
• Closing mechanisms
• Multiplexing? Might be optional for a v1
• Tower - layering
• Testing scenarios and protocol
• Feature Flag for flavors
• Make client send
• e2e polling/websocke testing
• Documentation

[codspeed-hq]

Merging this PR will regress 1 benchmark

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 4 improved benchmarks
❌ 1 regressed benchmark
✅ 82 untouched benchmarks

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
❌	Encode packet event on /	6.9 µs	8.4 µs	-18.14%
⚡	Decode packet ping/pong	3.2 µs	2.8 µs	+15.49%
⚡	Decode packet noop	3.3 µs	2.9 µs	+15.19%
⚡	Decode packet ping/pong upgrade	3.1 µs	2.8 µs	+13.82%
⚡	Decode packet message	3.4 µs	3.1 µs	+10.87%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing engineioxide-client-impl (c69be17) with main (9a10442)}