[AI] Expand Test Coverage - eldritch-core/strings

[google-labs-jules]

This PR increases test coverage for eldritch-core by adding a new test file tests/strings_extended_coverage.rs. It covers:

• splitlines with various arguments.
• title with mixed case and separators.
• strip, lstrip, rstrip with arguments.
• removeprefix and removesuffix.
• format edge cases.
• partition and rpartition.
• Unicode handling with codepoints and elems.

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PR created automatically by Jules for task 13929783739314624257 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 ⏱️
#439	✅	2980	2980	0	0	0	0	30.5s

Insights

Average Tests per Run	Total Flaky Tests	Total Failed	Slowest Test (p95)
2980	0	0	11.8s

Slowest Tests

Test 📝	Results 📊	Duration (avg) ⏱️	Duration (p95) ⏱️
eldritch-macros: tests::test_arg_parsing_option	3	3.9s	11.8s
eldritch-macros: tests::test_arg_parsing_option	3	3.9s	11.8s
eldritch-macros: tests::test_arg_parsing_option	3	3.9s	11.8s
eldritch-macros: tests::test_arg_parsing_str	3	3.8s	11.4s
eldritch-macros: tests::test_arg_parsing_str	3	3.8s	11.4s
eldritch-macros: tests::test_arg_parsing_str	3	3.8s	11.4s
eldritch: sys::dll_inject_impl::tests::test_dll_inject_simple	1	11.4s	11.4s
eldritch: sys::dll_reflect_impl::tests::test_dll_reflect_starlark	1	11.0s	11.0s
eldritch-macros: tests::test_expand_library_basic	3	3.6s	10.8s
eldritch-macros: tests::test_expand_library_basic	3	3.6s	10.8s

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

Github Test Reporter by CTRF 💚