fix: prevent paste boundary escapes and reflow content loss

[simota]

Summary

• Prevent nested bracketed-paste markers from ending a paste early. Removing an embedded marker could join the surrounding bytes into a new ESC[201~, leaving subsequent text outside the paste boundary. Sanitize the output suffix in a single pass so reconstructed markers are removed too.
• Preserve populated rows below the cursor when resizing columns and rows together, or when narrower columns produce more wrapped rows. Reflow now accounts for the last content row and moves displaced top rows into scrollback. For example, resizing a populated 10×4 terminal with the cursor at home to 11×3 keeps the fourth line instead of discarding it.

Five regression tests cover every marker split point, deeply nested markers, widening/narrowing during row shrink, wrapped content below the cursor, and erased trailing rows with saved-cursor preservation.

Test plan

• Confirmed the new bug reproductions fail before the fixes and pass afterward.
• cargo test -p noa-app -p noa-grid --lib --quiet
• cargo test --workspace --quiet (passed outside the sandbox to allow IPC loopback listeners)
• cargo fmt --all --check
• git diff --check

Validation uses deterministic paste-byte and terminal-grid assertions; no interactive macOS screenshot or recording was captured.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-05T00:04:32.281887Z	8b18090	PR opened

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