[presentation] Promote frontend and Workers packages with generated-app runtime smoke

[kang-heewon]

Priority

P1 - presentation runtime confidence

Problem

The frontend and Cloudflare Workers presentation surface remains alpha because package tests do not yet prove the generated-app runtime behavior users depend on: browser hydration, Vite output, Worker SSR, service-binding API routing, asset fallback, streaming response preservation, and env/context propagation.

Affected alpha packages:

• @croco/frontend-react
• @croco/frontend-vite
• @croco/frontend-cloudflare
• @croco/transports-cloudflare-workers

Evidence

Source of truth: trunk@9c2ac20.

• docs/package-catalog.json:234-236 and 251 list these packages as alpha.
• README.md:451 lists @croco/transports-cloudflare-workers as alpha with package tests.
• README.md:458-461 lists all frontend packages as alpha with package tests.
• packages/docs/src/content/docs/en/reference/presentation-runtime-support.md:8-10 says presentation packages can remain alpha when runtime smoke, output validation, diagnostics, or recovery paths are incomplete.
• packages/docs/src/content/docs/en/reference/presentation-runtime-support.md:38-44 names the exact beta gates for frontend-react, frontend-cloudflare, and frontend-vite.
• Generated API docs are missing for all four packages under packages/docs/src/content/docs/api/<package>/.

Desired Outcome

The presentation runtime packages can be promoted only when generated apps prove the production path for each claimed runtime, not just package-level helper behavior.

Proposed Implementation Path

• Add generated-app smoke for a fullstack profile that uses frontend-react, frontend-vite, frontend-cloudflare, and transports-cloudflare-workers together where applicable.
• Prove browser hydration and page data flow for frontend-react.
• Prove Vite config generation, optional Cloudflare peer behavior, browser build output, and SPA/meta-vite generated app build for frontend-vite.
• Prove Worker SSR, service-binding API routing, asset fallback, streaming preservation, env/context propagation, and clear failure behavior for frontend-cloudflare.
• Prove Worker request context bridge and published type surface for transports-cloudflare-workers.
• Add diagnostics/readiness or documented recovery paths for unsupported runtime capabilities.

Acceptance Criteria

• Generated-app smoke fails if hydration, page data flow, API routing, asset fallback, or Worker context propagation regresses.
• Streaming claims are backed by tests that assert response body preservation.
• Optional Cloudflare peer behavior is covered without requiring Cloudflare credentials in default CI.
• Package READMEs link to the smoke evidence and document unsupported runtime paths.
• Generated API docs exist or tracked short-lived exceptions are recorded before promotion.

Validation

• pnpm --filter @croco/frontend-react test
• pnpm --filter @croco/frontend-vite test
• pnpm --filter @croco/frontend-cloudflare test
• pnpm --filter @croco/transports-cloudflare-workers test
• pnpm create-croco-app:smoke
• pnpm package-entrypoints:smoke
• pnpm docs:catalog:check

Scope Boundaries

• Do not promise durable Worker ISR unless a Worker-safe durable cache adapter is supplied and tested.
• Do not require live Cloudflare deployment in default CI.
• Keep generated-app smoke deterministic and zero-credential by default.