refactor(markdown): Simplify table header detection logic

Remove unused `isSparkTableHeader` import and simplify condition
since spark tables are handled upstream by `coerceSparkTables`.

src/markdown/table.ts

@@ -1,5 +1,4 @@
 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
@@ -35,8 +34,12 @@ export default function markedTable(): MarkedExtension {
         let roll = "";
         let remix = "";
 
+        // Spark tables (dice-formula first column) are handled upstream by
+        // `coerceSparkTables` in the content registry — they're rewritten to
+        // `:md-table` directives before rendering. This renderer only handles
+        // label-based tables (md-table-label / md-roll-label / md-remix-label).
         const labelIndex = header.findIndex((cell) => {
-          if (cell.text === "md-roll-label" || isSparkTableHeader(cell.text)) {
+          if (cell.text === "md-roll-label") {
             roll = " roll=true";
             return true;
           } else if (cell.text === "md-remix-label") {