[go-server] Fix: param names clash with variables, added suffix

Created by: lwj5

Controller contains variables named query params and err. If the param name is any of the above, an error would occur.

Problem is isolated in the controllers, so I've added Param suffix to all paramName in the controller

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Hi @antihax @grokify @kemokemo @jirikuncar @ph4r5h4d, please help to take a look at this PR