Complete Economic Observatory MVP (ADAPTIVE-WP-0002)

Add file-based Bubble, Stripe, and OpenRouter importers; usage attribution,
cost allocation, pricing simulator, credit wallets, and recommendations in the
dashboard API. Document whynot-design UI workflow and archive the finished
workplan with all ten tasks marked done.

projects/coulomb-pricing/data/imports/openrouter-export.sample.json

@@ -0,0 +1,11 @@
+{
+  "usage": [
+    {
+      "period": "2026-06",
+      "user_id": "member-tegwick",
+      "model": "anthropic/claude-3-haiku",
+      "tokens": 48200,
+      "cost_usd": "0.06"
+    }
+  ]
+}