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/credit_wallets.json

@@ -0,0 +1,11 @@
+{
+  "version": 1,
+  "currency": "EUR",
+  "wallets": [
+    {
+      "member_id": "member-tegwick",
+      "monthly_allowance_eur": "2.00",
+      "note": "Observatory-only allowance for hybrid pricing experiments"
+    }
+  ]
+}