[Vector DB Project Type] Implement new onboarding designs

[seialkali]

Summary

Implements the new Vector DB project type onboarding designs based on the Figma specs. This PR restructures the onboarding flow to help developers with pre-computed embeddings reach their first hybrid search query quickly.

Key changes:

• Path selection screen: New landing page with two clear paths — "Generate vectors for me" (semantic_text) and "Store and search my vectors" (dense_vector)
• Connection bar: ES endpoint and API key are now always visible on every onboarding screen via the ConnectToProject component
• Step rail navigation: New sidebar showing progress through the Ingest → Search flow with contextual descriptions per path
• Refactored component structure: Extracted reusable components (OnboardingPanel, StepContent, StepLayout, StepRail) for better maintainability
• New language assets: Added SVG icons for supported client languages (Python, JavaScript, Go, Java, Rust, C#)
• Hook reorganization: Moved hooks to dedicated hooks/ directory

Test plan

• Verify path selection screen displays correctly with endpoint and API key
• Test "Generate vectors for me" path flows through ingest → search steps
• Test "Store and search my vectors" path flows through ingest → search steps
• Confirm API key copy button works, or "Generate API key" button opens connection details modal
• Verify "Skip the setup guide" button navigates to home
• Check step rail navigation updates correctly between steps
• Test responsive layout at different breakpoints

Made with Cursor

[infra-vault-gh-plugin-prod]

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