Fix scrolling over wrapped lines

[hgwr]

Summary

• keep window and cursor in sync when moving past long wrapped lines
• add regression test for scrolling past top wrapped lines

Testing

• cargo test --verbose
• cargo build --verbose
• pytest -n auto e2e --verbose

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https://chatgpt.com/codex/tasks/task_e_6896df2888f8832fa1d7cc80714f82e5

[gemini-code-assist]

Summary of Changes

Hello @hgwr, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

I've implemented a fix to improve the editor's scrolling behavior, specifically addressing issues where the cursor and window position would desynchronize when moving past long, wrapped lines. This change ensures that the editor maintains correct visual alignment and cursor placement, enhancing the overall navigation experience. Additionally, I've added a new end-to-end test to prevent similar issues from reappearing in the future.

Highlights

• Cursor and Window Synchronization: I've addressed an issue where the editor's window and cursor could become out of sync when navigating past long lines that wrap, ensuring a smoother and more predictable user experience.
• New Regression Test: I've introduced a new end-to-end regression test specifically designed to catch future regressions related to scrolling past wrapped lines, particularly when they appear at the top of the screen.

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[gemini-code-assist]

Code Review

This pull request fixes an issue with scrolling past wrapped lines by removing a call to move_end_of_line that had interfering side effects. A regression test is also added to cover this scenario. My review points out that while the scrolling is fixed, the underlying logic for cursor movement in NextLine is still not fully correct for wrapped lines and is inconsistent with PreviousLine. I've suggested a refactoring to address this for more robust behavior.