feat(shellv2): improve autocomplete and docstring tooltips

[KCarretto]

This PR improves the shellv2 terminal experience by fine-tuning the autocomplete and docstring menus. It adjusts the tooltip hover delays to be uniformly 250ms, ensuring they stay open slightly longer when navigating away from them but close quickly enough not to be obtrusive. The autocomplete menu now automatically closes when typing ( or when the exact function name has been fully typed. A Ctrl+Space shortcut was also added to manually trigger the autocomplete menu, displaying a "no suggestions" indicator if no completions are found.

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PR created automatically by Jules for task 6452961494475872398 started by @KCarretto

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[github-actions]

Summary

Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
2727    ±0	2727    ±0	0    ±0	0    ±0	0    ±0	0    ±0	1ms    ±0

Previous Results

Build 🏗️	Result 🧪	Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
#1429	✅	2727	2727	0	0	0	0	43.2s

Insights

Average Tests per Run	Total Flaky Tests	Total Failed	Slowest Test (p95)
2727	0	0	6.0s

Slowest Tests

Test 📝	Results 📊	Duration (avg) ⏱️	Duration (p95) ⏱️
TestDockerExecutor_Build_ContextCancellation	1	6.0s	6.0s
eldritch-libsys: std::dll_inject_impl::tests::test_dll_inject_simple	1	5.2s	5.2s
TestInteractiveShell	1	5.0s	5.0s
TestOtherStreamOutput	1	5.0s	5.0s
imix::bin/imix: install::tests::test_install_execution	3	1.6s	4.7s
imix::bin/imix: install::tests::test_install_execution	3	1.6s	4.7s
imix::bin/imix: install::tests::test_install_execution	3	1.6s	4.7s
TestDockerExecutor_Build_SimpleEcho	1	3.4s	3.4s
imix::bin/imix: tests::task_tests::test_task_streaming_output	3	3.0s	3.0s
imix::bin/imix: tests::task_tests::test_task_streaming_output	3	3.0s	3.0s

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

Github Test Reporter by CTRF 💚