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/06.README/default.md

@@ -0,0 +1,22 @@
+---
+title: 'StartingLineProductions (STLP) — STEP0'
+menu: 'StartingLineProductions (STLP) — STEP0'
+---
+
+# StartingLineProductions (STLP) — STEP0
+
+Goal
+- Get STLP to cashflow fast using a simple weekly execution cadence. Keep back office minimal; ship and sell.
+
+Assets (from your description)
+- Craft room: Glowforge (laser), CNC, vinyl cutter, pro photo printer, Dream Box (broad craft materials/tools), sewing machines, embroidery machine.
+- EE lab: reflow oven and electronics bench for small-batch assembly/prototyping.
+- Location: Pflugerville, TX (home-based).
+
+Deliverables to produce in STEP0
+- `questions.md` — capture specifics (capacity, services, pricing, constraints).
+- `offers.md` — offer ladder + SKUs (fast to sell).
+- `marketing-sales-plan.md` — channels + first-week actions.
+- `website-tech-plan.md` — MVP site, intake, payments, analytics.
+- `90-day-plan.md` — 0→cash roadmap with weekly rhythm.
+- `week-1-plan.md` — concrete Tue–Fri tasks and KPIs.