(SP: 1) [Frontend] Add Go, GraphQL, NestJS, and NuxtJS category icons and styles

[ViktorSvertoka]

Description

Add visual category support for Go, GraphQL, NestJS, and NuxtJS across the Q&A and Quiz interfaces.

Scope

• add SVG icons for Go, GraphQL, NestJS, and NuxtJS
• register the new categories in the shared category registry
• assign brand-aligned accent, hover, active, and glow styles
• expose the generated styles through the existing category style API
• preserve compatibility with all current category consumers

Acceptance Criteria

• Go, GraphQL, NestJS, and NuxtJS appear in category navigation
• each category renders its correct SVG icon
• hover and active states use the corresponding brand color
• new categories are available in both Q&A and Quiz
• category keys remain strictly typed from the shared registry
• SVG validation, ESLint, and category tests pass

Technical Notes

Display order:

• Go: 30
• GraphQL: 31
• NestJS: 32
• NuxtJS: 33

Accent colors:

• Go: #00ADD8
• GraphQL: #E434AA
• NestJS: #DF234F
• NuxtJS: #00C58E