tui-textarea/.github/pull_request_template.md

## Problem
Describe the user-visible problem this PR solves.

## Change Summary
List the key code and behavior changes.

## Test Evidence
- [ ] `cargo fmt --check`
- [ ] `cargo clippy --all-targets -- -D warnings`
- [ ] `cargo check`
- [ ] `cargo test`

## Breaking Changes
Describe any API or behavior changes that may break existing users.