Update Zig to latest master version

[hulto]

Updated the Zig version in .devcontainer/Dockerfile to the latest master build (0.16.0-dev.2984+cb7d2b056). Verified the latest version via the official Zig download index and ensured that all Go and Rust tests pass with the change.

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PR created automatically by Jules for task 6976732986628400398 started by @hulto

[google-labs-jules]

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[github-actions]

Summary

Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
2840    ±0	2840    ±0	0    ±0	0    ±0	0    ±0	0    ±0	1ms    ±0

Previous Results

Build 🏗️	Result 🧪	Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
#1881	✅	2840	2840	0	0	0	0	40.7s

Insights

Average Tests per Run	Total Flaky Tests	Total Failed	Slowest Test (p95)
2840	0	0	6.0s

Test Changes

0 test added, 0 removed

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	5.1s	5.1s
TestInteractiveShell	1	5.0s	5.0s
TestOtherStreamOutput	1	5.0s	5.0s
TestDockerExecutor_Build_SimpleEcho	1	4.3s	4.3s
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
imix::bin/imix: tests::task_tests::test_task_streaming_output	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 💚