Hygiene: SCOPE stance sentence, stack/architecture stubs, first-session archive

Record the published fail-closed PEP stance in SCOPE, fill the agent
stack and architecture stubs from the shipped layout, and retire the
first-session protocol now that USER-WP-0001–0024 exist.

Assistant: grok
Assistant-Session: 01a04cea-f0d6-7ab3-9ffd-881eb6bea6cb

.claude/rules/stack-and-commands.md

@@ -1,19 +1,28 @@
 ## Stack
 
-<!-- TODO: Fill in language, frameworks, and key dependencies -->
-- **Language:**
-- **Key deps:**
+- **Language:** Python 3.12+ (`requires-python = ">=3.12"`)
+- **Layout:** `pyproject.toml` + `src/user_engine/` + stdlib `unittest`
+- **Runtime:** optional extras only — `psycopg[binary]` (Postgres store),
+  `PyJWT[crypto]` (OIDC). Core domain and in-memory adapters have no
+  third-party deps.
+- **Entry point:** `user-engine-portal` → `user_engine.runtime:main`
 
 ## Dev Commands
 
 ```bash
-# TODO: Fill in the standard commands for this repo
+# Orient
+cat .custodian-brief.md
+cat INTENT.md
+cat SCOPE.md
+ls workplans/
 
-# Install dependencies
+# Tests and layer check
+make test
+make check-layer
 
-# Run tests
+# Optional extras
+pip install -e ".[runtime]"
 
-# Lint / type check
-
-# Build / package (if applicable)
+# After workplan or registry edits
+statehub fix-consistency
 ```