fix(dev): proxy content registry to CLI server

Inline spark tables (role=spark-table) live in the content registry, but the
rsbuild dev proxy forwarded only /__COMPLETIONS.json and
/__CONTENT_INDEX.json. The registry fetch fell back to the SPA index.html,
so /roll resolved the inline CSV as HTML and csv-parse failed with an
invalid opening quote.

Load the registry before publishing the loaded completions state so a roll
cannot fire while inline content is still unresolvable.

docs/development.md

@@ -253,7 +253,7 @@ npm test -- --watch
 - Web 前端：rsbuild 开发服务器，端口 **5173**
 - CLI 内容服务器：`tttk serve`，端口 **3000**（内容 API + Journal）
 
-rsbuild 会把 `/__CONTENT_INDEX.json`、`/__COMPLETIONS.json`、`/content`、`/.ttrpg` 代理到 CLI 的
+rsbuild 会把 `/__CONTENT_INDEX.json`、`/__COMPLETIONS.json`、`/__CONTENT_REGISTRY.json`、`/content`、`/.ttrpg` 代理到 CLI 的
 3000 端口，因此必须先启动 CLI，否则前端拿不到内容。
 
 ### Web 开发