fix: Repair data pipeline with StatCan CMHC rental data

- Add StatCan CMHC parser to fetch rental data from Statistics Canada API
- Create year spine (2014-2025) as time dimension driver instead of census
- Add CMA-level rental and income intermediate models
- Update mart_neighbourhood_overview to use rental years as base
- Fix neighbourhood_service queries to match dbt schema
- Add CMHC data loading to pipeline script

Data now flows correctly: 158 neighbourhoods × 12 years = 1,896 records
Rent data available 2019-2025, crime data 2014-2024

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

dbt/models/intermediate/int_rentals__toronto_cma.sql

@@ -0,0 +1,25 @@
+-- Intermediate: Toronto CMA rental metrics by year
+-- Aggregates rental data to city-wide averages by year
+-- Source: StatCan CMHC data at CMA level
+-- Grain: One row per year
+
+with rentals as (
+    select * from {{ ref('stg_cmhc__rentals') }}
+),
+
+-- Pivot bedroom types to columns
+yearly_rentals as (
+    select
+        year,
+        max(case when bedroom_type = 'bachelor' then avg_rent end) as avg_rent_bachelor,
+        max(case when bedroom_type = '1bed' then avg_rent end) as avg_rent_1bed,
+        max(case when bedroom_type = '2bed' then avg_rent end) as avg_rent_2bed,
+        max(case when bedroom_type = '3bed' then avg_rent end) as avg_rent_3bed,
+        -- Use 2-bedroom as standard reference
+        max(case when bedroom_type = '2bed' then avg_rent end) as avg_rent_standard,
+        max(vacancy_rate) as vacancy_rate
+    from rentals
+    group by year
+)
+
+select * from yearly_rentals