feat: Unify spark table detection and content resolution

Export isSparkTableHeader from content-registry and use it in both CLI
and frontend table parsing. Add resolveContentRef to resolve content
references consistently. Write processed registry content back to the
file index so browser mode renders identically to CLI mode.

src/markdown/table.ts

@@ -1,4 +1,5 @@
 import type { MarkedExtension, Tokens } from "marked";
+import { isSparkTableHeader } from "../cli/content-registry";
 
 /**
  * 将表格数据转换为 CSV 格式字符串
@@ -35,7 +36,7 @@ export default function markedTable(): MarkedExtension {
         let remix = "";
 
         const labelIndex = header.findIndex((cell) => {
-          if (cell.text === "md-roll-label" || cell.text.match(/(\d+)?d\d+/)) {
+          if (cell.text === "md-roll-label" || isSparkTableHeader(cell.text)) {
             roll = " roll=true";
             return true;
           } else if (cell.text === "md-remix-label") {