Add message reader quick navigation

[keyang556]

Closes #81.

Summary

• Add Page Up/Page Down navigation that jumps ten reader entries at a time and clamps safely at the first or last entry.
• Add Ctrl+Home and Ctrl+End shortcuts to jump directly to the first and last reader entry.
• Handle the quick-jump keys at the dialog level, add regression coverage, and document the shortcuts in English, Traditional Chinese, Japanese, and Thai.

Validation

• uv run --no-project --with pytest python -m pytest — 163 passed
• uv run --no-project --with ruff ruff check addon\\appModules\\_messageReader.py tests\\test_message_reader_parser.py — passed

Greptile Summary

此變更為訊息閱讀器加入 Page Up／Page Down 十項跳轉，以及 Ctrl+Home／Ctrl+End 前往首尾項目的操作，並同步更新英文、日文、泰文與繁體中文說明。

已透過實際鍵盤事件路徑確認：清單內的快速跳轉會移動至預期位置；到達首尾時會維持在有效範圍並提供既有提示；空清單不會變更位置或引發例外；未按 Ctrl 的 Home 會繼續交由原有按鍵處理。未發現需要修正的問題。

Confidence Score: 5/5

T-Rex Logs

What T-Rex did

• Ran keyboard navigation validation using a stubbed NVDA/wx dialog by sending PageUp, PageDown, Ctrl+Home, and Ctrl+End to the message reader.
• Compared to before, the changed implementation consumes the shortcuts and delivers the expected navigation results, including ten-item list jumps, start/end jumps, and boundary prompts; an empty input retains the current position, and Home without Ctrl is passed to the original handler.
• Authored the executable validation source and saved both the before- and after-change command outputs as artifacts.
• Compared pre-change capture to post-change capture: the pre-change state skipped all four quick-navigation shortcuts and left the position unchanged; the post-change state consumed the shortcuts and produced the expected positions and feedback with no leaks.

_{Ran code and verified through T-Rex}

_{Reviews (1): Last reviewed commit: "Add message reader quick navigation" | Re-trigger Greptile}