Add fullscreen editor and proportional resize

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.

js/background.js

@@ -23,6 +23,89 @@ function updateContextMenu(id, update) {
   })
 }
 
+function pageReadSelectionText() {
+  try {
+    const active = document.activeElement
+    const isTextInput =
+      active &&
+      (active.tagName === 'TEXTAREA' ||
+        (active.tagName === 'INPUT' &&
+          /^(text|search|url|tel|email|password)$/i.test(active.type || 'text')))
+
+    if (isTextInput && typeof active.selectionStart === 'number' && typeof active.selectionEnd === 'number') {
+      return String(active.value || '').slice(active.selectionStart, active.selectionEnd).replace(/\r\n?/g, '\n')
+    }
+
+    const sel = window.getSelection && window.getSelection()
+    if (!sel) return ''
+    return String(sel.toString() || '').replace(/\r\n?/g, '\n')
+  } catch (_) {
+    return ''
+  }
+}
+
+function getSelectionTextFromTab(tabId, fallbackText) {
+  return new Promise((resolve) => {
+    const fallback = typeof fallbackText === 'string' ? fallbackText : ''
+    if (!tabId || !chrome.scripting || typeof chrome.scripting.executeScript !== 'function') {
+      resolve(fallback)
+      return
+    }
+
+    try {
+      chrome.scripting.executeScript(
+        {
+          target: { tabId },
+          func: pageReadSelectionText
+        },
+        (results) => {
+          if (chrome.runtime.lastError) {
+            resolve(fallback)
+            return
+          }
+          const first = Array.isArray(results) ? results[0] : null
+          const text = first && typeof first.result === 'string' ? first.result : ''
+          resolve(text || fallback)
+        }
+      )
+    } catch (_) {
+      resolve(fallback)
+    }
+  })
+}
+
+function tryOpenActionPopup(tab) {
+  try {
+    if (!chrome.action || typeof chrome.action.openPopup !== 'function') return
+    const windowId = tab && typeof tab.windowId === 'number' ? tab.windowId : undefined
+
+    const open = () => {
+      try {
+        if (typeof windowId === 'number') {
+          chrome.action.openPopup({ windowId }, () => void chrome.runtime.lastError)
+        } else {
+          chrome.action.openPopup({}, () => void chrome.runtime.lastError)
+        }
+      } catch (_) {
+        // best-effort only
+      }
+    }
+
+    // Avoid: "Cannot show popup for an inactive window".
+    if (typeof windowId === 'number' && chrome.windows && typeof chrome.windows.update === 'function') {
+      chrome.windows.update(windowId, { focused: true }, () => {
+        void chrome.runtime.lastError
+        open()
+      })
+      return
+    }
+
+    open()
+  } catch (_) {
+    // best-effort only
+  }
+}
+
 let cachedUiLanguage = null
 let cachedOverrideMessages = null
 
@@ -93,35 +176,43 @@ chrome.storage.onChanged.addListener((changes, areaName) => {
   refreshContextMenus()
 })
 
-chrome.contextMenus.onClicked.addListener((info) => {
-  let tempCont = ''
-  switch (info.menuItemId) {
-    case 'Memos-send-selection':
-      tempCont =
-        info.selectionText +
-        '\n' +
-        `[Reference Link](${info.linkUrl || info.pageUrl})` +
-        '\n'
-      break
-    case 'Memos-send-link':
-      tempCont = (info.linkUrl || info.pageUrl) + '\n'
-      break
-    case 'Memos-send-image':
-      tempCont = `![](${info.srcUrl})` + '\n'
-      break
-  }
-
-  chrome.storage.sync.get(
-    { open_action: 'save_text', open_content: '' },
-    function (items) {
+chrome.contextMenus.onClicked.addListener((info, tab) => {
+  const appendContent = (tempCont, { openPopup } = { openPopup: false }) => {
+    chrome.storage.sync.get({ open_action: 'save_text', open_content: '' }, function (items) {
       if (items.open_action === 'upload_image') {
         t('picPending').then((m) => alert(m))
-      } else {
-        chrome.storage.sync.set({
+        return
+      }
+
+      chrome.storage.sync.set(
+        {
           open_action: 'save_text',
           open_content: items.open_content + tempCont
-        })
-      }
-    }
-  )
+        },
+        function () {
+          if (openPopup) tryOpenActionPopup(tab)
+        }
+      )
+    })
+  }
+
+  if (info.menuItemId === 'Memos-send-selection') {
+    const ref = info.linkUrl || info.pageUrl
+    const tabId = tab && tab.id
+
+    getSelectionTextFromTab(tabId, info.selectionText).then((selectionText) => {
+      const tempCont = selectionText + '\n' + `[Reference Link](${ref})` + '\n'
+      appendContent(tempCont, { openPopup: true })
+    })
+    return
+  }
+
+  if (info.menuItemId === 'Memos-send-link') {
+    appendContent((info.linkUrl || info.pageUrl) + '\n')
+    return
+  }
+
+  if (info.menuItemId === 'Memos-send-image') {
+    appendContent(`![](${info.srcUrl})` + '\n')
+  }
 })