[Odometer] Build Odometer merged image flow

[Julesssss]

Odometer Project implementation Phase 1

Tracking issue

Part of the Add Odometer mileage to NewDot project (design doc)

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Task

Implement these changes from the Odometer design doc:

• Add merge image feature to App for combining start/end images
• Add combined image preview to Confirm Details page

[melvin-bot]

@Julesssss, @DylanDylann, @jakubkalinski0 Huh... This is 4 days overdue. Who can take care of this?

[melvin-bot]

@Julesssss, @DylanDylann, @jakubkalinski0 Still overdue 6 days?! Let's take care of this!

[melvin-bot]

@Julesssss, @DylanDylann, @jakubkalinski0 Now this issue is 8 days overdue. Are you sure this should be a Daily? Feel free to change it!