Add liquidity tracking, budget, and platform cost history

Restore operator platform costs (Bubble, domains, Stripe) with monthly
history from March 2025 and member payments from November 2025. Track
€1,000 starting budget, cumulative burn, and remaining liquidity in the
economics dashboard. Document LQ requirements in REQUIREMENTS.md.

projects/coulomb-pricing/README.md

@@ -6,19 +6,26 @@ Generic adaptive-pricing framework concepts belong in the repository root
 (`INTENT.md`, `docs/`, `research/`, `registry/`). Execution tracking:
 `workplans/ADAPTIVE-WP-0002-economic-observatory-mvp.md`.
 
+Liquidity and cost requirements: `REQUIREMENTS.md`.
+
 ## Sprint 1 — Economic Foundations
 
 The `observatory/` package loads JSON registries and produces **Economics
-Dashboard v1** metrics:
+Dashboard v1** with platform-cost history, member payments, and budget burn.
 
 | Registry | File |
 |----------|------|
+| Budget (€1,000 start) | `data/budget.json` |
 | Product model | `data/product.json` |
 | Pricing models | `data/pricing-models.json` |
-| Costs | `data/costs.json` |
-| Revenue | `data/revenue.json` |
+| Platform costs + history | `data/costs.json` |
+| Member payments | `data/revenue.json` |
 | Membership | `data/membership.json` |
 
+**Current reality:** platform costs from March 2025; sole member payments from
+November 2025. Operator is **burning liquidity** — platform spend exceeds
+subscription intake. Customer cost-pass-through billing is not active.
+
 ### Commands
 
 ```bash
@@ -28,6 +35,5 @@ python3 -m observatory --period 2026-06
 python3 -m observatory --period 2026-06 --output reports/economics-2026-06.md
 ```
 
-**Current registry state:** one active member (founder), €8.99/month revenue, no
-running costs recorded. Bubble (Sprint 2) and Stripe (Sprint 3) importers will
-replace manual entries when integrations land.
+Manual registries will be replaced by Bubble (Sprint 2), Stripe (Sprint 3), and
+OpenRouter (Sprint 4) importers.