fix(docs): escape MDX JSX openers in generated reference tables

[lukaisailovic]

Problem

The docs build failed on main:

[plugin fumadocs-mdx:mdx] .../reference/manifest.mdx
273:62-273:488: Expected a closing tag for `<CODE>` before the end of `tableData`

build runs gen:reference first, which regenerates manifest.mdx. A schema field description reads …use 'currency:<CODE>' (e.g. currency:RSD), and the generator emitted that prose verbatim into a table cell. MDX parsed <CODE> as a JSX tag, found no closer, and aborted the build.

Fix

cell() in gen-reference.ts only escaped the pipe, even though its header comment promised cells "stay free of unescaped { } < >". It now also escapes MDX's JSX/expression openers < and {, so any bracket-bearing description renders as literal text. renderType never emits these characters, so type cells are unaffected.

Regenerated manifest.mdx is included — the committed copy was also stale, so the diff additionally reflects current schema (daterange default, query search, currency:<CODE> formats).

Verification

• pnpm gen:reference → currency:\<CODE> in output
• pnpm build in apps/docs completes (prerender + postbuild succeed)