feat: add GeoJSON parsers and choropleth map visualization

- Add geo.py parser module with CMHCZoneParser, TRREBDistrictParser,
  and NeighbourhoodParser for loading geographic boundaries
- Add coordinate reprojection support (EPSG:3857 to WGS84)
- Organize geo data in data/toronto/raw/geo/ directory
- Add CMHC zones GeoJSON (31 zones) for rental market choropleth
- Add Toronto neighbourhoods GeoJSON (158) as purchase market proxy
- Update callbacks with real CMHC 2024 rental data
- Add sample purchase data for all 158 neighbourhoods
- Update pre-commit config to exclude geo data files

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

.pre-commit-config.yaml

@@ -7,7 +7,7 @@ repos:
       - id: check-yaml
       - id: check-added-large-files
         args: ['--maxkb=1000']
-        exclude: ^data/raw/
+        exclude: ^data/(raw/|toronto/raw/geo/)
       - id: check-merge-conflict
 
   - repo: https://github.com/astral-sh/ruff-pre-commit