Introduce a fullscreen editor mode and a proportional resize handle for the memo editor. Updates include:
- UI: add fullscreen button and resize handle to popup.html and related i18n keys for en/ja/ko/zh_CN.
- CSS: styles for .memo-editor, fullscreen state, and #editor-resize-handle, plus layout tweaks for fullscreen.
- Background: enhance context menu handler to retrieve selection text from the active tab using chrome.scripting.executeScript, support opening the extension popup programmatically (tryOpenActionPopup), and factor appendContent logic.
- Oper: implement isFullscreenMode(), openFullscreenTab(), proportional editor resize logic with pointer events (initProportionalEditorResize), focus handling adjustments, and init call. Added helper focusTextareaToEnd().
- Manifest: request scripting and windows permissions required for selection injection and window focus.
These changes enable sending accurate selection text from web pages, allow users to open a fullscreen editor tab, and provide a draggable, proportional resize experience in the popup editor.
Introduce a runtime UI language switcher and add Japanese/Korean locale support. Added _locales/ja and _locales/ko messages, updated en and zh_CN message files with new language-related keys and sendImage label. Implemented dynamic i18n handling: new i18n.js supports override messages, persistent uiLanguage in storage, and emits i18n:changed; background.js now loads override locales, updates context menu titles and listens for storage changes. Integrated dayjs locales (js/ja.js, js/ko.js) and made oper.js use a unified msg() helper and react to language changes. Added language selector UI in popup.html and styling in css/main.css.
Add the original page/link as a Markdown reference when sending selected text via the context menu. background.js now appends `[Reference Link](...)` using info.linkUrl or info.pageUrl; manifest version bumped to 2026.03.06; README changelog updated to note the new right-click behavior.