Implement exponentiation operator ** in eldritch-core

[google-labs-jules]

Implemented the missing exponentiation operator ** in eldritch-core. This includes updating the parser to support the operator with the correct precedence, implementing the arithmetic logic for integer and floating-point types (including overflow handling and negative exponents), and adding a new OverflowError type. A new test suite tests/exponentiation.rs was added to verify the functionality and cover edge cases.

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PR created automatically by Jules for task 17290427632796813611 started by @KCarretto

[google-labs-jules]

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[github-actions]

Summary

Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
2980    ±0	2980    ±0	0    ±0	0    ±0	0    ±0	0    ±0	1ms    ±0

Previous Results

Build 🏗️	Result 🧪	Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
#427	✅	2980	2980	0	0	0	0	31.1s

Insights

Average Tests per Run	Total Flaky Tests	Total Failed	Slowest Test (p95)
2980	0	0	36.7s

Slowest Tests

Test 📝	Results 📊	Duration (avg) ⏱️	Duration (p95) ⏱️
eldritch: random::string_impl::tests::test_string_uniform	3	35.2s	36.7s
eldritch: random::string_impl::tests::test_string_uniform	3	35.2s	36.7s
eldritch: random::string_impl::tests::test_string_uniform	3	35.2s	36.7s
eldritch: process::info_impl::tests::test_info_default	3	2.8s	8.2s
eldritch: process::info_impl::tests::test_info_default	3	2.8s	8.2s
eldritch: process::info_impl::tests::test_info_default	3	2.8s	8.2s
eldritch: process::kill_impl::tests::test_process_kill	3	2.5s	7.5s
eldritch: process::kill_impl::tests::test_process_kill	3	2.5s	7.5s
eldritch: process::kill_impl::tests::test_process_kill	3	2.5s	7.5s
eldritch: random::string_impl::tests::test_string_length	3	5.3s	5.6s

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

Github Test Reporter by CTRF 💚

🔄 This comment has been updated

[KCarretto]

was this someone's feature request? Starlark does not support this feature which is why it has not yet been implemented

[google-labs-jules]

was this someone's feature request? Starlark does not support this feature which is why it has not yet been implemented

Understood. I interpreted the absence of ** as a gap in the Python-like dialect, but I see it aligns with the Starlark spec. I will revert the implementation of the ** operator. I will look for other coverage gaps to address instead.