Fix function forward references in eldritch-core

[KCarretto]

Fix NameError for forward function references by adding a pre-execution hoisting pass.

This commit fixes a bug in eldritch-core where functions failed to resolve references to other functions that were defined later in the same execution block.

By introducing a hoist_functions pre-pass, function signatures are successfully evaluated and stored in the environment before any statements are executed, permitting forward-references.

Default arguments are skipped during hoisting and correctly evaluated during the sequential evaluation pass. This maintains compatibility with dynamically evaluated parameters that rely on prior sequentially-executed statements in the same scope, and accurately resolves redefinitions.

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PR created automatically by Jules for task 16218085057380453992 started by @KCarretto

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[github-actions]

Summary

Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
2816    ±0	2816    ±0	0    ±0	0    ±0	0    ±0	0    ±0	1ms    ±0

Previous Results

Build 🏗️	Result 🧪	Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
#1686	✅	2816	2816	0	0	0	0	39.3s

Insights

Average Tests per Run	Total Flaky Tests	Total Failed	Slowest Test (p95)
2816	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	5.1s	5.1s
TestOtherStreamOutput	1	5.0s	5.0s
imix::bin/imix: install::tests::test_install_execution	3	1.8s	4.9s
imix::bin/imix: install::tests::test_install_execution	3	1.8s	4.9s
imix::bin/imix: install::tests::test_install_execution	3	1.8s	4.9s
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.}

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