Add Agent Settings UI for AI search

[Mbeaulne]

Tophatting

Manual tophatting recommended because this PR adds a settings screen.

1. Turn on the Components V2 beta flag.
2. Open Settings → Agent Configuration.
3. Try saving without a model and confirm the inline error is shown.
4. Enter a provider URL, API key, and model id, then click “Test connection”.

What changed

Adds the Agent Settings screen for configuring AI search.

Users can enter:

• API base URL
• API key
• model id

The screen can test whether the provider is reachable and whether the model exists.

Why

Components V2 AI search should work with a user-provided OpenAI-compatible API. This keeps credentials out of the app bundle and lets users choose their own provider/model.

Test plan

• Turn on the Components V2 beta flag
• Open Settings → Agent Configuration
• Try saving without a model and confirm inline validation appears
• Enter a provider URL/key/model and click “Test connection”
• Run pnpm exec vitest run src/routes/Settings/sections/AgentSettings.test.tsx
• Run pnpm run typecheck --pretty false

[github-actions]

🎩 Preview

A preview build has been created at: 05-27-agent-settings-ui/0417a6f

[Mbeaulne]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• Adds AI-generated component descriptions to Components V2 #2337
• Add AI rerank and detail actions to Components V2 #2323
• Add multi-source Components V2 search and filters #2322
• Add Components V2 route shell #2319
• Add component search support utilities #2318
• Extract shared component detail view #2317
• Add natural-language component rerank service #2321
• Add Agent Settings UI for AI search #2320 👈 (View in Graphite)
• Add BYOK component search settings hook #2316
• Add component search index service #2315
• master

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