/promote — gated investment-opportunity surface, scroll-deck pro…

New surface: `/promote`

Added a multi-tenant opportunity-promotion surface for sharing investment opportunities and syndicates with a small circle of co-investors.
Three-surface architecture: public index at /promote, gated opportunity hub at /promote/[slug], gated materials at /promote/[slug]/{type}/{format?}/{version?}.
URL grammar: decks carry both format (scroll | static | interactive) and version dimensions; memos carry only version. Computed by lib/promote/urls.ts so YAML never has to declare hrefs.
Public index renders OG + Twitter card meta so iMessage / WhatsApp DMs unfurl with a brand image and headline.

New Astro middleware at src/middleware.ts reads a signed promote_session cookie and gates every path matching ^/promote/[^/]+/.+$. Locked requests are rewritten to the hub's locked-state render — deck and memo content never assemble for unauthenticated callers.
Server-validated passcode flow at src/pages/api/promote/unlock.ts. Codes are scrypt-hashed against an environment-configured master hash; an optional PROMOTE_OVERRIDE_CODES_JSON map enables per-opportunity codes without code changes.
Cookie shape: HMAC-SHA256-signed payload { unlocked, exp, scope }, HttpOnly, SameSite=Lax, Secure in production, scoped to /promote. TTL: 7 days, sliding renewal with a polished "signed in for 7 days on this device" toast on first unlock.
PROMOTE_DEV_BYPASS=1 accepts any code locally for development.
Env reads use process.env first with import.meta.env fallback — Astro 6 doesn't reliably surface non-PUBLIC_* vars via import.meta.env at runtime.

MaterialsChooser component conditionally renders by material count: 0 → 404, 1 → auto-redirect (hub becomes a router), 2-3 → vertical card list, 4+ → 2-column grid.
Each Material declares type, optional format, title, description, primary, status, default_version. Drafts hidden in production.
Sibling formats of the same type (e.g. deck.scroll + deck.static) render as separate chooser cards.

Copied PageAsDeckWrapper.astro pattern from sites/calmstorm-decks and adapted to mpstaton-site's two-tier semantic tokens. Provides scroll-snap container, keyboard nav (↑ ↓ Home End PgUp PgDn), double-click upper/lower half navigation, fixed {n}/{N} counter bottom-right, and IntersectionObserver reveal-on-intersect for .reveal-item children.
New PromotionDeckLayout.astro wraps the deck wrapper with minimal chrome (back-link to hub + session toast).
Section components live under src/layouts/sections/promote/{slug}/deck/{format}/v{N}/ so a single opportunity can host multiple formats and multiple versions side-by-side.
Loader at lib/promote/sections.ts uses import.meta.glob to discover sections at build time per (slug, format, version) triple.

Memos render through @lossless-group/lfm (parseMarkdown → MDAST → existing AstroMarkdown.astro + Sources.astro). Reuses the citations pipeline already wired for context-v document rendering.
Versions resolve from memo/v{N}.md (or legacy memo.md for v1) — lib/promote/memos.ts handles fallback.

Each opportunity is a directory at src/content/promote/{slug}/:
- opportunity.yaml — metadata: company name, status (active | closing-soon | closed | paused), logo, accent color, materials list, gate config.
- variants.yaml — registry of (format, version) deck pairs and per-format default version.
- data.yaml — shared structured data the deck composes against.
- narratives/{NN}-{slug}.md — one markdown per slide with frontmatter + prose ("what this slide is", "why it's here", "visual hierarchy").
- memo/v{N}.md — versioned memo content.
Loader at lib/promote/opportunities.ts reads via fs, parses YAML with the existing yaml dep, caches in-process.

New .gitignore patterns at sites/mpstaton-site/.gitignore: opportunity content under src/content/promote/, src/layouts/sections/promote/, and public/promote/ is local-only, except for directories prefixed with _ which are committed.
Pattern: _demo, _template, _scaffold etc. become committable scaffolding seeds that future opportunities copy from. Real opportunity slugs (anything not starting with _) stay on-disk only.
Verified with git check-ignore: real opportunity content is invisible to git add; _demo remains stageable.

OpportunityCard.astro renders a card per active opportunity. Anchored on the symbolic mark (appIcon / wordmark fragment), not the full logo — full logo is reserved for the OG share image.
StatusPill.astro shows Active (default), Closing soon (emphasised), Closed (kept on the index below active opportunities so prospects can see what they missed), or Paused.
Index sorts: Closing soon first, then Active, then Paused, with Closed rendered separately at the bottom.

Workflow targeted at 3-5 minute cycles to ship a new deck variant once narratives + data are sharp.
Recipe lifted from calmstorm-decks: pre-sharpened narrative copy → shared YAML data → established theme tokens → single rendering primitive (PageAsDeckWrapper).
Net effect: brand-new opportunities take an hour or two (narrative is the slow step). Additional variants of an already-modelled opportunity approach single-session economics.

_demo opportunity scaffold at src/content/promote/_demo/ with three placeholder section components, a placeholder memo, and listed_in_index: false. Hidden from the public index but reachable at /promote/_demo for end-to-end smoke testing of the gate, chooser, deck, and memo flow.

New blueprint at astro-knots/context-v/blueprints/Build-a-Promotion-Surface-for-Investment-Opportunities.md. Frames the architecture, hard-gate posture, materials chooser, variant iteration loop, content model, and decisions audit trail. Sibling to Build-a-Fundraise-Deck-Workspace.md and Confidential-Content-Access-Control-Blueprint.md.

.env.example extended with PROMOTE_SESSION_SECRET (HMAC signing key, hex 32 bytes), PROMOTE_MASTER_CODE_HASH (scrypt of master code), PROMOTE_OVERRIDE_CODES_JSON (per-slug overrides), PROMOTE_DEV_BYPASS (local development convenience).
src/env.d.ts declares App.Locals.promote typing for the middleware-set unlock flag.