refactor: multi-dashboard structural migration

- Rename dbt project from toronto_housing to portfolio
- Restructure dbt models into domain subdirectories:
  - shared/ for cross-domain dimensions (dim_time)
  - staging/toronto/, intermediate/toronto/, marts/toronto/
- Update SQLAlchemy models for raw_toronto schema
- Add explicit cross-schema FK relationships for FactRentals
- Namespace figure factories under figures/toronto/
- Namespace notebooks under notebooks/toronto/
- Update Makefile with domain-specific targets and env loading
- Update all documentation for multi-dashboard structure

This enables adding new dashboard projects (e.g., /football, /energy)
without structural conflicts or naming collisions.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Makefile

@@ -1,11 +1,12 @@
-.PHONY: setup docker-up docker-down db-init load-data seed-data run test dbt-run dbt-test lint format ci deploy clean help logs run-detached etl-toronto
+.PHONY: setup docker-up docker-down db-init load-data load-all load-toronto load-toronto-only seed-data run test dbt-run dbt-test lint format ci deploy clean help logs run-detached etl-toronto
 
 # Default target
 .DEFAULT_GOAL := help
 
 # Environment
-PYTHON := python3
-PIP := pip
+VENV := .venv
+PYTHON := $(VENV)/bin/python3
+PIP := $(VENV)/bin/pip
 DOCKER_COMPOSE := docker compose
 
 # Architecture detection for Docker images
@@ -79,16 +80,23 @@ db-reset: ## Drop and recreate database (DESTRUCTIVE)
 	@sleep 3
 	$(MAKE) db-init
 
-load-data: ## Load Toronto data from APIs, seed dev data, run dbt
+# Domain-specific data loading
+load-toronto: ## Load Toronto data from APIs
 	@echo "$(GREEN)Loading Toronto neighbourhood data...$(NC)"
 	$(PYTHON) scripts/data/load_toronto_data.py
-	@echo "$(GREEN)Seeding development data...$(NC)"
+	@echo "$(GREEN)Seeding Toronto development data...$(NC)"
 	$(PYTHON) scripts/data/seed_amenity_data.py
 
-load-data-only: ## Load Toronto data without running dbt or seeding
+load-toronto-only: ## Load Toronto data without running dbt or seeding
 	@echo "$(GREEN)Loading Toronto data (skip dbt)...$(NC)"
 	$(PYTHON) scripts/data/load_toronto_data.py --skip-dbt
 
+# Aggregate data loading
+load-data: load-toronto ## Load all project data (currently: Toronto)
+	@echo "$(GREEN)All data loaded!$(NC)"
+
+load-all: load-data ## Alias for load-data
+
 seed-data: ## Seed sample development data (amenities, median_age)
 	@echo "$(GREEN)Seeding development data...$(NC)"
 	$(PYTHON) scripts/data/seed_amenity_data.py
@@ -119,15 +127,15 @@ test-cov: ## Run pytest with coverage
 
 dbt-run: ## Run dbt models
 	@echo "$(GREEN)Running dbt models...$(NC)"
-	cd dbt && dbt run --profiles-dir .
+	@set -a && . ./.env && set +a && cd dbt && dbt run --profiles-dir .
 
 dbt-test: ## Run dbt tests
 	@echo "$(GREEN)Running dbt tests...$(NC)"
-	cd dbt && dbt test --profiles-dir .
+	@set -a && . ./.env && set +a && cd dbt && dbt test --profiles-dir .
 
 dbt-docs: ## Generate dbt documentation
 	@echo "$(GREEN)Generating dbt docs...$(NC)"
-	cd dbt && dbt docs generate --profiles-dir . && dbt docs serve --profiles-dir .
+	@set -a && . ./.env && set +a && cd dbt && dbt docs generate --profiles-dir . && dbt docs serve --profiles-dir .
 
 # =============================================================================
 # Code Quality