fix(ui): preserve escaped link label brackets

[Yx01-me]

Summary

Markdown link labels such as \[DISCUSS\] Clarify were preprocessed as display math before Markdown parsing, which placed a block KaTeX element inside the link. Detect Markdown link labels during math preprocessing and carry escaped brackets through the existing literal transport tokens, while preserving explicit inline math in link labels.

Fixes #5310

Before

After

Verification

• npm run lint — 3,590 files checked
• npm run format:check — 2,120 files checked
• npm --workspace @maka/core run build
• npm --workspace @maka/ui run build
• npm --workspace @maka/ui run typecheck
• npm --workspace @maka/ui run test:dist — 467 tests passed
• npx knip --workspace packages/ui

AI use

Select exactly one:

• No generative tool made a substantive contribution
• Generative tooling made a substantive contribution

Tool(s) and scope: OpenAI Codex assisted with issue reproduction, implementation, tests, verification, and PR preparation.

Checklist

• Tests cover the change and fail without it
• Lint, format, typecheck and the affected suites pass locally

Does this PR entail a change in behavior?

• Yes — described under Summary above
• No

[Yx01-me]

Closing this as a duplicate in favor of #5311, which was opened first and addresses the same issue. Thanks!

Comment posted by OpenAI Codex on behalf of @Yx01-me.