feat: add category filter bar to the Hub for improved model discoverability

[JoelJose23]

Describe Your Changes

• Implemented a sticky category filter bar in the Hub to enhance model discoverability.
• Added CATEGORIES definitions with regex-based matching for model names and descriptions to dynamically organize the catalog.
• Integrated activeCategory state and filtering logic into HubContent to enable real-time model list updates.
• Added a useEffect hook to ensure the virtualized list scrolls to the top (rowVirtualizer.scrollToOffset(0)) when switching categories, improving UX.
• Ensured that initiating a text search automatically resets the category filter to "All" to prevent accidental empty search results.
• A short Video and a screenshot showcasing the changes have been attached below for your convenience.

Screencast.From.2026-06-24.19-32-08.mp4

Fixes Issues

• None

Self Checklist

• Added relevant comments, esp in complex areas
• Updated docs (for bug fixes / features)
• Created issues for follow-up changes or refactoring needed

[JoelJose23]

While browsing the Hub, I noticed that as the library of open models grows, finding a specific type of model (like a dedicated coding assistant or a vision model) requires a lot of manual scrolling and reading through individual descriptions. I realized that grouping them dynamically by use-case would save users time and make the Hub feel much more intuitive. This PR is my approach to fixing that discoverability gap.

[JoelJose23]

Hey team! I noticed the CI pipeline hit a total of 24 linting and strict TypeScript compilation errors across the desktop matrix builds.

I went through the initial logs and managed to patch the first 7 upstream compilation bottlenecks found inside the core package (core.ts, extension.ts, LocalOAIEngine.ts, etc.) by stripping the unused imports/variables causing the TS6133/TS6192 fatal failures.
Tested the final build to make sure everything worked just fine/