Update process.list() field to "principal" and increase HostProcess cmd size

[KCarretto]

Updated eldritch process.list() (both real and fake implementations) to return "principal" instead of "username". Updated HostProcess schema to use Text for cmd field to allow larger command lines. Added integration test verifying report.process_list().

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PR created automatically by Jules for task 13893460706475092467 started by @KCarretto

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[github-actions]

Summary

Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
2610    ±0	2610    ±0	0    ±0	0    ±0	0    ±0	0    ±0	1ms    ±0

Previous Results

Build 🏗️	Result 🧪	Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
#1031	✅	2610	2610	0	0	0	0	36.7s

Insights

Average Tests per Run	Total Flaky Tests	Total Failed	Slowest Test (p95)
2610	0	0	5.2s

Slowest Tests

Test 📝	Results 📊	Duration (avg) ⏱️	Duration (p95) ⏱️
eldritch-libsys: std::dll_inject_impl::tests::test_dll_inject_simple	1	5.2s	5.2s
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
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
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 💚