Add BYOK component search settings hook

[Mbeaulne]

Tophatting

No manual tophatting required. This PR only adds the settings storage hook and unit tests.

What changed

Adds a small settings hook for Components V2 AI search configuration.

The hook stores these values in browser localStorage:

• API base URL
• API key
• model id

It also handles old saved config that used thinkingModel.

Why

AI search uses a bring-your-own-key setup. This PR only adds the storage layer; it does not add UI or call an AI provider yet.

Test plan

• Run pnpm exec vitest run src/hooks/useComponentSearchSettings.test.ts
• Run pnpm run typecheck --pretty false
• Confirm empty settings report as not configured
• Confirm saved settings load back from localStorage

[Mbeaulne]

• Adds AI-generated component descriptions to Components V2 #2337 : 2 dependent PRs (#2350 , #2351 )
• 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
• Add BYOK component search settings hook #2316 👈 (View in Graphite)
• Add component search index service #2315
• master

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[github-actions]

🎩 Preview

A preview build has been created at: 05-27-agent-settings-ai-rerank-service/1fb6bb7

[morgan-wowk]

🤖 AI-assisted review — one finding on the settings update() write path.

[morgan-wowk]

Approved with comments

[Mbeaulne]

Merge activity

• Jun 5, 2:37 PM UTC: A user started a stack merge that includes this pull request via Graphite.
• Jun 5, 2:43 PM UTC: Graphite rebased this pull request as part of a merge.
• Jun 5, 2:46 PM UTC: @Mbeaulne merged this pull request with Graphite.