[ENG-274] Add landing page, market pages, and header toolbar to frontend

[xbtmatt]

Summary

• Ensure the frontend has properly encapsulated and populated environment variables for RPC url, Cluster, etc
• Add a landing page with Links to each active dropset market
• Add individual dropset market pages with a slug
• Add a header toolbar

[linear]

ENG-274

[Copilot]

Pull request overview

This PR introduces initial frontend navigation and market browsing UX: a landing page that lists markets and links into per-market pages via slugged routes, plus shared layout elements (header, styling, and React Query setup).

Changes:

• Added a markets landing page and per-market route (/market/[slug]) with slug resolution helpers.
• Introduced React Query providers + hooks, and stubbed market query functions.
• Added a global header and expanded global CSS styling for the new pages/components.

Reviewed changes

Copilot reviewed 16 out of 17 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
frontend/src/lib/slug.ts	Adds prefix-map generation and slug resolution for market routes.
frontend/src/lib/rpc.ts	Placeholder file intended for RPC/env encapsulation (currently empty).
frontend/src/lib/queries/fetch-market.ts	Adds stubbed single-market fetch helper and type.
frontend/src/lib/queries/fetch-all-markets.ts	Adds stubbed all-markets fetch helper and type.
frontend/src/lib/providers.tsx	Introduces React Query provider (and devtools) wiring.
frontend/src/lib/hooks/use-market.ts	Adds useMarket query hook.
frontend/src/lib/hooks/use-all-markets.ts	Adds useAllMarkets query hook.
frontend/src/components/header.tsx	Adds a sticky header with basic navigation links.
frontend/src/app/page.tsx	Replaces the starter home page with a markets table + links to market pages.
frontend/src/app/market/[slug]/page.tsx	Adds server route for a slugged market page + metadata generation.
frontend/src/app/market/[slug]/market-view.tsx	Adds client-side market detail view using React Query.
frontend/src/app/layout.tsx	Wraps app with Providers/Header and adds favicon metadata.
frontend/src/app/info/page.tsx	Adds placeholder Info page.
frontend/src/app/repo/page.tsx	Adds placeholder Repo page.
frontend/src/app/team/page.tsx	Adds placeholder Team page.
frontend/src/app/globals.css	Adds styling for header, page layout, and market table/detail components.
frontend/package.json	Adjusts Biome lint script invocation.

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[Copilot]

Pull request overview

Copilot reviewed 43 out of 45 changed files in this pull request and generated 7 comments.

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

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[Copilot]

Pull request overview

Copilot reviewed 16 out of 18 changed files in this pull request and generated 4 comments.

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

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[xbtmatt]

Addressing comments