CARS.md: Added a year column

[ugtthis]

• Easier to find the relevant year when there is a separate column
• Comma body and Tesla models didn’t have a year so I added “-“ to represent the blank year

How I verified changes:

• Scanned through the diff multiple times making sure intended changes were made accurately
• Used chat gpt to compare random lines of the old table with the new table to make sure I didn’t change a year to a different year by accident

Vid comparing changes

comparing-table-changes.mp4

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