VSA fix haml helper paths passed to the frontend

What does this MR do and why?

This MR addresses #340276 (closed).

Previously we passed helper paths for API requests from the backend, these paths would then be appended with a json extension when required, but we can construct the helper paths on the backend for VSA to include the json extension and remove this extra step.

Additionally, this MR moves the project cycle analytics data to a helper and adds related rspec tests.

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