feat: convert from mdbook to Grav format

- Rename src/ to pages/
- Add Grav frontmatter to markdown files
- Create numbered folder structure
- Remove mdbook-specific files

Migration from mdbook to Grav CMS.

pages/03.90-day-plan/default.md

@@ -0,0 +1,28 @@
+---
+title: 'STLP — 90‑Day Plan (Draft)'
+menu: 'STLP — 90‑Day Plan (Draft)'
+---
+
+# STLP — 90‑Day Plan (Draft)
+
+Phase 1: Weeks 1–2 (Cash-in)
+- Offers: launch 3 entry SKUs + 2 core offers.
+- Site: single-page with order/quote form + Stripe links.
+- Channels: Google Business Profile, IG/TikTok reels, Nextdoor/FB intro.
+- Goal: first 3–10 paid orders; $500–$1,500 revenue.
+
+Phase 2: Weeks 3–6 (Repeatability)
+- Expand SKUs based on demand; add FAQs and gallery.
+- Tighten pricing/minimums; add rush fee policy.
+- Begin B2B outreach for signage/embroidery in local niches.
+- Goal: weekly revenue consistency; 5+ orders/week.
+
+Phase 3: Weeks 7–12 (Scale foundation)
+- Add storefront if necessary; formalize intake and file handling.
+- Light CRM capture; basic email list for repeat buyers.
+- Partnership pilots (schools/PTAs, local businesses).
+- Goal: $3k–$5k/month run rate by week 12.
+
+Weekly rhythm
+- Mon admin; Tue offer/pipeline; Wed MVP; Thu publish/promote; Fri close/validate.
+- Persist/pivot/switch rules apply every Friday.