Description

Problem
After opening a folder containing files in the editor, if you open a file via the global search on the left, close it without making any edits, a prompt "Do you want to save changes?" will still pop up. The tab was incorrectly marked as unsaved because Muya's setMarkdown() triggers a change event with re-serialized content that can differ from the on-disk content (e.g. trailing newlines, line endings).

Solution

1. Normalized comparison
   When deciding whether content changed, compare both the incoming markdown and the previous markdown using the same trailing-newline normalization (adjustTrailingNewlines), so purely normalization differences do not set isSaved = false.

2. Ignore first content change after opening
   For tabs created via NEW_TAB_WITH_CONTENT (e.g. open from search or file tree), set a flag ignoreNextContentChangeForSaveStatus so the first change event from Muya after setMarkdown() is not treated as a user edit. The flag is always cleared after handling each content change so subsequent real edits are still detected.

Files changed

• src/renderer/store/editor.js: added mutation CLEAR_IGNORE_NEXT_CONTENT_CHANGE_FOR_SAVE_STATUS; set ignoreNextContentChangeForSaveStatus in NEW_TAB_WITH_CONTENT; in LISTEN_FOR_CONTENT_CHANGE, compare using normalized old markdown and skip setting unsaved when the flag is set; clear the flag after every content change.

中文说明

问题
在编辑器中打开一个拥有文件的文件夹后，通过左侧全局搜索打开文件后，未做任何编辑直接关闭，仍会弹出「是否保存更改」的提示。原因是 Muya 的 setMarkdown() 会触发一次 change 事件，其内容为重新序列化后的 markdown，与磁盘内容可能不完全一致（如末尾换行、换行符等），导致被误判为未保存。

修复

1. 归一化后再比较
   判断内容是否变化时，对「当前内容」和「打开时的内容」都做相同的末尾换行归一化再比较，避免仅因归一化差异被标为未保存。
2. 打开后忽略第一次 content change
   对通过 NEW_TAB_WITH_CONTENT 打开的标签（如从搜索/文件树打开），设置 ignoreNextContentChangeForSaveStatus，使 Muya 在 setMarkdown() 之后触发的第一次 change 不视为用户编辑。每次处理 content change 后都会清除该标记，确保之后的真实编辑仍会被正确标为未保存。

涉及文件

• src/renderer/store/editor.js：新增 mutation、在打开带内容的 tab 时设标记、在 content change 中做归一化比较与“忽略首次”逻辑，并在每次处理完后清除标记。