feat(editor): paste and drop images into Markdown files (#489)

Pasting or dropping an image into a Markdown editor saves it beside the document in `assets/` and inserts a URL-encoded relative link as one undo step, in local and remote projects. Existing names get numbered suffixes; the folder and clipboard name pattern are in Settings › Editor › General. Non-Markdown editors, text paste and other dropped files keep their behavior.

Fixes #308

src/platform/editorSettings.ts

@@ -67,6 +67,8 @@ export const EDITOR_EXTRA_DEFAULTS = {
   boldFontWeight: 700,
   general: {
     wheelZoom: false,
+    markdownImageFolder: "assets",
+    markdownImageNamePattern: "image-{timestamp}",
     dragAndDrop: true,
     caretScroll: "minimize",
     softWrapFiles: "*.md; *.txt; *.rst; *.adoc",

src/platform/locales/text/zh.json

@@ -5215,5 +5215,13 @@
   "Pull request #{n} exists for current branch {branch}": "当前分支 {branch} 存在拉取请求 #{n}",
   "Show Review Diff": "显示审查差异",
   "Pull Request branch update failed": "拉取请求分支更新失败",
-  "#{n} on {branch}": "#{n} 位于 {branch}"
+  "#{n} on {branch}": "#{n} 位于 {branch}",
+  "Markdown Images": "Markdown 图片",
+  "Image folder": "图片文件夹",
+  "Relative to the Markdown file.": "相对于 Markdown 文件。",
+  "Image name pattern": "图片名称格式",
+  "For clipboard images: {timestamp} becomes YYYYMMDD-HHmmss. Source file names are preserved.": "剪贴板图片中的 {timestamp} 替换为 YYYYMMDD-HHmmss。保留源文件名称。",
+  "Image folder must be relative.": "图片文件夹必须使用相对路径。",
+  "Image exceeds 16 MB.": "图片超过 16 MB。",
+  "Cannot insert image": "无法插入图片"
 }