feat(lesson-preparation): 浮动工具条 + 锚点/inline-node/对话体样式

src/modules/lesson-preparation/components/paper-editor/paper-toolbar.tsx

@@ -0,0 +1,47 @@
+"use client";
+
+import type { Editor } from "@tiptap/react";
+
+interface Props {
+  editor: Editor;
+}
+
+/**
+ * V4 浮动工具条：粘在纸顶部，毛玻璃半透明。
+ * 仅在编辑器聚焦时显示（由父组件控制）。
+ */
+export function PaperToolbar({ editor }: Props) {
+  const btn = (
+    label: string,
+    action: () => void,
+    isActive: boolean,
+    className: string,
+    title: string,
+  ) => (
+    <button
+      type="button"
+      onClick={action}
+      title={title}
+      className={`lp-tb-btn ${isActive ? "is-active" : ""} ${className}`}
+      onMouseDown={(e) => e.preventDefault()} // 防止失焦
+    >
+      {label}
+    </button>
+  );
+
+  return (
+    <div className="lp-paper-toolbar">
+      {btn("B", () => editor.chain().focus().toggleBold().run(), editor.isActive("bold"), "b", "Bold")}
+      {btn("I", () => editor.chain().focus().toggleItalic().run(), editor.isActive("italic"), "i", "Italic")}
+      <span className="lp-tb-divider" />
+      {btn("H1", () => editor.chain().focus().toggleHeading({ level: 1 }).run(), editor.isActive("heading", { level: 1 }), "h1", "Heading 1")}
+      {btn("H2", () => editor.chain().focus().toggleHeading({ level: 2 }).run(), editor.isActive("heading", { level: 2 }), "h2", "Heading 2")}
+      <span className="lp-tb-divider" />
+      {btn("•", () => editor.chain().focus().toggleBulletList().run(), editor.isActive("bulletList"), "ul", "Bullet list")}
+      {btn("1.", () => editor.chain().focus().toggleOrderedList().run(), editor.isActive("orderedList"), "ol", "Ordered list")}
+      <span className="lp-tb-divider" />
+      {btn('"', () => editor.chain().focus().toggleBlockquote().run(), editor.isActive("blockquote"), "quote", "Quote")}
+      {btn("—", () => editor.chain().focus().setHorizontalRule().run(), false, "hr", "Divider")}
+    </div>
+  );
+}