Upgrade TypeScript 5.9 to 6.0

[smartlabsAT]

Description

TypeScript 6.0 is available (currently on 5.9.3).

Packages to update

• typescript: 5.9.3 -> 6.0.2

Breaking Changes to investigate

• Review TypeScript 6.0 release notes
• Check compiler options compatibility
• Verify tsup compatibility

Tasks

• Read TypeScript 6.0 migration guide
• Update typescript
• Fix type errors if any
• Verify build (pnpm build)
• Verify tests (pnpm test:ci)
• Verify lint (pnpm lint)