* fix(docs): add .mintignore to exclude non-MDX-safe files
roadmap-pro.md contains curly braces ({hash}, {userId}) that Mintlify's
MDX parser interprets as JSX expressions, causing deploy failures.
Exclude it along with PRESS_KIT.md and Docs_To_Review/ (internal files
not in navigation).
* fix(docs): enhance MDX lint to catch curly braces and .md files
Mintlify parses all docs/ files as MDX, treating {expr} as JSX
expressions. The existing lint only checked .mdx files for bare angle
brackets. Now also checks:
- .md files (Mintlify processes these too)
- Bare curly braces {word} outside code fences/spans
- Respects docs/.mintignore for excluded files
