Normalize repo metadata and sync docs

.claude/rules/architecture.md

@@ -1,7 +1,37 @@
 ## Architecture
 
-<!-- TODO: Describe the key design decisions and component structure.
-     Key modules, data flows, external integrations, state machines, etc. -->
+The repo has two layers:
+
+1. Root framework layer
+- `INTENT.md`, `docs/`, `research/`, and `registry/` define the generic
+  adaptive-pricing vocabulary, lifecycle model, and roadmap.
+- `workplans/` is the repo-native source of truth for tracked work (ADR-001).
+
+2. Project implementation layer
+- `projects/coulomb-pricing/` contains the first concrete deployment:
+  Coulomb Social's Economic Observatory MVP.
+- `observatory/` is a small Python package that reads JSON ledgers and
+  registries from `data/`, computes economics snapshots, and serves a local UI.
+
+Current Coulomb data flow:
+- `data/*.json` ledgers and registries
+- `observatory/load.py` parses JSON into dataclasses
+- `observatory/ledger.py` builds monthly cost rows
+- `observatory/economics.py` computes liquidity, margins, and snapshots
+- `observatory/allocation.py`, `usage.py`, `pricing_context.py`,
+  `simulator.py`, `credits.py`, and `recommendations.py` derive higher-level
+  pricing views
+- `observatory/api.py` assembles the dashboard payload
+- `observatory/__main__.py` renders the Markdown report
+- `observatory/server.py` exposes `/api/dashboard` and serves `ui/`
+
+External integrations are file-based in MVP:
+- Bubble export importer
+- Stripe export importer
+- OpenRouter export importer
+
+The internal model and ledgers are the source of truth. Provider exports feed
+the ledgers; they do not replace them.
 
 ## Quick Reference