docs(prd): add PRD 0007 — batteries-included Profullstack sites (#264)

Files the OpenPRD proposal for `moshcode site init <name>`: a trusted,
in-source initializer that turns a claimed Moshpit name into a working
full-stack application, alongside a new bundled `profullstack` template.

The design keeps the existing security boundary intact — `template
install` stays copy-only and never executes template code, while all
provisioning (Turso, CoinPay, systemd, web server) lives in trusted
Moshcode source behind explicit approval.

Generated stack: Bun + SolidStart with one set of TSX routes reused for
SSR and hydrated SPA navigation, `@libsql/client` against local SQLite or
hosted Turso, a versioned `/api/v1`, CoinPay OAuth/OIDC with PKCE, hashed
sessions and scoped API tokens, a blog with RSS, and a default-on
queue/release auto-blog that makes no paid AI calls.

Because Moshpit names sit outside the public DNS root and the gateway
strips cookies and `Authorization`, the app serves two logical origins:
the plain Moshpit origin is public and read-only, and a separate CA-valid
`AUTH_ORIGIN` is the only one that issues sessions.

Filed as 0007 (the pasted draft carried 0005, already taken by the hosted
resolver PRD). Index regenerated with `regenerateIndex()`, which also
picked up existing drift: 0005 and 0006 were missing from the table and
0004 had since moved to Accepted.

Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: ralyodio