Update provincial tax parameters for 2024-2025 with CPI uprating

[MaxGhenis]

Summary

• Add CPI index files for Ontario, British Columbia, and Quebec
• Update tax rate files to use uprating metadata instead of manual indexing
• Follow PolicyEngine-US pattern of using actual CPI values rather than uprating factors

Changes

New CPI Index Files

• Added - Ontario CPI (2002=100 base)
• Added - British Columbia CPI (2002=100 base)
• Added - Quebec CPI (2002=100 base)

Updated Tax Rate Files

• Modified Ontario, BC, and Quebec tax rate files to use uprating metadata
• Tax brackets now automatically index based on provincial CPI
• Removed manually calculated 2024-2025 values in favor of uprating

References

• Statistics Canada Consumer Price Index tables
• Provincial government tax rate announcements
• Government indexation percentages (ON: 4.5%/2.8%, BC: 5.0%/2.8%, QC: 5.08%/2.85%)

Related Issues

Addresses #506, #507, #508 (provincial tax updates)

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Co-Authored-By: Claude noreply@anthropic.com