## Summary
When `WORKFLOW_PUBLIC_MANIFEST=1` is set, each framework builder exposes the workflow manifest at `/.well-known/workflow/v1/manifest.json` via the most appropriate mechanism for the framework:
- **Next.js**: Copies manifest to `public/.well-known/workflow/v1/manifest.json` (served as a static file)
- **SvelteKit**: Copies manifest to `static/.well-known/workflow/v1/manifest.json` (served as a static file)
- **Vercel Build Output API** (example workbench): Copies manifest to `.vercel/output/static/.well-known/workflow/v1/manifest.json` (served as a static file)
- **Nitro** (vite, hono, express, fastify, nuxt, nitro-v2, nitro-v3): Registers a virtual handler that reads and serves the manifest JSON
- **Astro**: Generates a `manifest.json.js` page route that returns the manifest JSON
- **NestJS**: Adds a `@Get('manifest.json')` endpoint on the `WorkflowController` (gated by the env var at runtime)
### Other changes
- `BaseBuilder.createManifest()` now returns the manifest JSON string so framework builders can use it
- Added `shouldExposePublicManifest` getter to `BaseBuilder`
- Fixed Astro `LocalBuilder` which was missing the `createManifest()` call that all other framework builders have
- Removed unused `public/` directory and static file copy from the example workbench build script
- Added `WORKFLOW_PUBLIC_MANIFEST` to `turbo.json` build task env so Vercel builds can access it
- Added generated manifest paths to `.gitignore`
Peter Wielander