feat(shellv2): implement websocket reconnection logic and status indicator

[KCarretto]

This PR implements automatic WebSocket reconnection logic for the Shell V2 page.

Changes include:

• HeadlessWasmAdapter now handles reconnection attempts with a backoff strategy and exposes connection status updates.
• useShellTerminal hook consumes the connection status, updating the UI state and preventing user input when the connection is lost.
• ShellStatusBar now features a visual indicator (icons) for the current connection status.
• Added unit tests for ShellStatusBar to ensure correct rendering of connection states.

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PR created automatically by Jules for task 4884011573793862373 started by @KCarretto

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[github-actions]

Summary

Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
2714    ±0	2714    ±0	0    ±0	0    ±0	0    ±0	0    ±0	1ms    ±0

Previous Results

Build 🏗️	Result 🧪	Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
#1358	✅	2714	2714	0	0	0	0	492268h 8m

Insights

Average Tests per Run	Total Flaky Tests	Total Failed	Slowest Test (p95)
2714	0	0	5.6s

Slowest Tests

Test 📝	Results 📊	Duration (avg) ⏱️	Duration (p95) ⏱️
TestDockerExecutor_Build_ContextCancellation	1	5.6s	5.6s
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	4.6s
imix::bin/imix: install::tests::test_install_execution	3	1.6s	4.6s
imix::bin/imix: install::tests::test_install_execution	3	1.6s	4.6s
imix::bin/imix: tests::task_tests::test_task_eprint_behavior	3	3.0s	3.0s
imix::bin/imix: tests::task_tests::test_task_eprint_behavior	3	3.0s	3.0s
imix::bin/imix: tests::task_tests::test_task_eprint_behavior	3	3.0s	3.0s

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

Github Test Reporter by CTRF 💚