Prefix Shell V2 Output with Truncated Input

[KCarretto]

This change updates the tavern backend shell handler to include the input command as a prefix in the websocket output messages sent to the frontend. This provides context in the Shell V2 terminal, allowing users to associate output with specific commands. The input is truncated to 64 characters to maintain readability. The implementation handles both interactive (real-time streaming via portals) and non-interactive (polled from database) modes, ensuring consistent behavior. Existing integration tests were updated, and a new test case for truncation was added.

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PR created automatically by Jules for task 5341438117760528229 started by @KCarretto

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[github-actions]

Summary

Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
2608    ±0	2608    ±0	0    ±0	0    ±0	0    ±0	0    ±0	1ms    ±0

Previous Results

Build 🏗️	Result 🧪	Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
#1032	✅	2608	2608	0	0	0	0	36.4s

Insights

Average Tests per Run	Total Flaky Tests	Total Failed	Slowest Test (p95)
2608	0	0	5.1s

Slowest Tests

Test 📝	Results 📊	Duration (avg) ⏱️	Duration (p95) ⏱️
eldritch-libsys: std::dll_inject_impl::tests::test_dll_inject_simple	1	5.1s	5.1s
TestDockerExecutor_Build_ContextCancellation	1	5.1s	5.1s
TestInteractiveShell	1	5.1s	5.1s
TestOtherStreamOutput	1	5.0s	5.0s
imix::bin/imix: install::tests::test_install_execution	3	1.2s	3.4s
imix::bin/imix: install::tests::test_install_execution	3	1.2s	3.4s
imix::bin/imix: install::tests::test_install_execution	3	1.2s	3.4s
TestDockerExecutor_Build_SimpleEcho	1	3.1s	3.1s
imix::bin/imix: tests::task_tests::test_task_streaming_error	3	3.0s	3.0s
imix::bin/imix: tests::task_tests::test_task_streaming_error	3	3.0s	3.0s

_{🎉 No failed tests in this run. | 🍂 No flaky tests in this run.}

Github Test Reporter by CTRF 💚