Add state-hub v0.1 — local-first state service for the Custodian

Implements the first live layer of the Custodian cognitive infrastructure:
PostgreSQL schema, FastAPI REST API, FastMCP stdio server, and Observable
Framework telemetry dashboard.

- state-hub/: full stack (docker-compose, FastAPI, Alembic, MCP server, dashboard)
- 5 DB tables: topics, workstreams, tasks, decisions, progress_events
- 11 MCP tools + 5 resources registered in .mcp.json
- Observable dashboard: Overview, Workstreams, Decisions, Progress pages
- CLAUDE.md: session protocol (get_state_summary / add_progress_event ritual)
- ~/.claude/CLAUDE.md: global cross-project reference to the hub
- scripts/pull_image.py: WSL2 TLS-resilient Docker image downloader

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

infra/docker-compose.yml

@@ -0,0 +1,33 @@
+services:
+  postgres:
+    image: postgres:16-alpine
+    restart: unless-stopped
+    ports:
+      - "127.0.0.1:5432:5432"
+    environment:
+      POSTGRES_DB: ${POSTGRES_DB:-custodian}
+      POSTGRES_USER: ${POSTGRES_USER:-custodian}
+      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD}
+    volumes:
+      - pg_data:/var/lib/postgresql/data
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U ${POSTGRES_USER:-custodian} -d ${POSTGRES_DB:-custodian}"]
+      interval: 5s
+      timeout: 5s
+      retries: 5
+
+  pgadmin:
+    image: dpage/pgadmin4:latest
+    profiles: ["tools"]
+    restart: unless-stopped
+    ports:
+      - "127.0.0.1:5050:80"
+    environment:
+      PGADMIN_DEFAULT_EMAIL: ${PGADMIN_EMAIL:-admin@local.dev}
+      PGADMIN_DEFAULT_PASSWORD: ${PGADMIN_PASSWORD:-admin}
+    depends_on:
+      postgres:
+        condition: service_healthy
+
+volumes:
+  pg_data: