Refine connection exception for internal control flow

[cclilshy]

Redefine ConnectionException as an internal control-flow exception and introduce event-driven lifecycle callbacks (onClose, onReadableEnd, onWritableEnd) to provide clear connection state management and robust error handling.

The previous ConnectionException was ambiguously used for both internal control flow and application-level errors, leading to potential deadlocks in the event loop and unclear user interaction. This refactoring ensures the reactor can reliably terminate connections on fatal I/O errors while empowering users with explicit, event-based notifications for connection lifecycle events, including half-close scenarios.

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[cursor]

Cursor Agent can help with this pull request. Just @cursor in comments and I'll start working on changes in this branch.
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[cursor]

I refactored stream-related exceptions, primarily replacing ConnectionException with TransportException for broader transport errors and introducing TransportTimeoutException. I also refined stream closing logic and fixed a CloseEvent constructor issue, improving overall stream robustness and error handling.

• I replaced most usages of Ripple\Stream\Exception\ConnectionException with Ripple\Stream\Exception\TransportException across src/Proc/Session.php, src/Socket.php, src/Stream.php, src/Worker/Worker.php, src/Worker/WorkerProcess.php, and tests/UnixTest.php for more general transport error handling.
• I introduced Ripple\Stream\Exception\TransportTimeoutException in src/Socket.php for specific SSL handshake timeouts, providing clearer error differentiation.
• I modified src/Stream.php to improve emitCloseEvent by extracting the ConnectionAbortReason from ConnectionException when available, ensuring accurate close event details.
• I fixed the src/Stream/CloseEvent.php constructor to explicitly assign the timestamp property, resolving a potential issue with readonly properties and the null coalescing assignment operator.
• I adjusted Stream::write in src/Stream.php to only suspend coroutines waiting for buffer clearance if there is actual data in the buffer, preventing unnecessary suspensions.
• I added a new test file test_fix.php to validate the CloseEvent constructor fix and the internal usage of ConnectionException.

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[cclilshy]

@cursor review