Update Zig version to latest master

[hulto]

This change updates the Zig version in the .devcontainer/Dockerfile to the latest master version (0.16.0-dev.3028+a85495ca2). This was done to ensure the Docker build CI remains up-to-date with the latest Zig toolchain. I have verified the change by reading the Dockerfile and running the project's Go and Rust tests to ensure no regressions were introduced.

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PR created automatically by Jules for task 3048240678379876928 started by @hulto

[google-labs-jules]

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[github-actions]

Summary

Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
2893	2892	1	0	0	0	1ms

Previous Results

Build 🏗️	Result 🧪	Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
#1905	❌	2893	2892	1	0	0	0	492993h 45m

Insights

Average Tests per Run	Total Flaky Tests	Total Failed	Slowest Test (p95)
2893	0	1	5.5s

Fail Rate

Fail Rate	0.03%

Test 📝	Results 📊	Passed ✅	Failed ❌	Fail Rate (%) 📈
TestReportFile	1	0	1	100.00    ↑100.00

Failed Tests

Failed Tests
❌ TestReportFile === RUN TestReportFile grpc.go:98: failed to serve grpc: closed --- FAIL: TestReportFile (0.20s) Trace: No trace available

Test Changes

0 test added, 0 removed

Slowest Tests

Test 📝	Results 📊	Duration (avg) ⏱️	Duration (p95) ⏱️
TestDockerExecutor_Build_ContextCancellation	1	5.5s	5.5s
eldritch-libsys: std::dll_inject_impl::tests::test_dll_inject_simple	1	5.1s	5.1s
TestInteractiveShell	1	5.1s	5.1s
TestOtherStreamOutput	1	5.0s	5.0s
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_output	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
imix::bin/imix: tests::task_tests::test_task_eprint_behavior	3	3.0s	3.0s

_{🍂 No flaky tests in this run.}

Github Test Reporter by CTRF 💚