Cardano Updates

feat: serve dashboard-api docs at /dashboard-api/

Adds a `rewrites` rule routing `docs.blockfrost.io/dashboard-api/*` to a
standalone Vercel project hosting the Blockfrost Dashboard API
documentation, plus a 308 redirect from the bare `/dashboard-api` to the
trailing-slash form (mirroring the existing `/midnight` pattern). An
explicit rewrite for the trailing-slash index is included separately
because Vercel's path matcher treats `:path*` as one-or-more in practice,
so the bare `/dashboard-api/` would otherwise 404.

This repo only hosts the path under the shared `docs.blockfrost.io`
domain; the spec and Scalar build live in the separate project and
deploy independently. README updated under Development with a short note
on the architecture.

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

The `/dashboard-api/:path*` pattern alone doesn't match the bare
trailing-slash request (Vercel's path matcher treats `:path*` as
"one or more segments" in practice, not zero-or-more), so visiting
`/dashboard-api/` produced a Vercel NOT_FOUND. Adding an explicit
rewrite for the index path makes the root work; the wildcard rule
continues to handle nested paths (`/openapi.yaml`, etc.).

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

Adds a Vercel rewrite forwarding `docs.blockfrost.io/dashboard-api/*`
to the standalone dashboard-api docs project
(https://blockfrost-dashboard-api-docs.vercel.app), and a 308 redirect
from the bare `/dashboard-api` path to the trailing-slash form —
matching the existing `/midnight` pattern.

The dashboard-api spec + docs live in the blockfrost-dashboard-api repo
and deploy independently. This repo just proxies the path under the
shared `docs.blockfrost.io` host.

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>