Refactor :with_observation and :with_description query parameters

[nimmolo]

• DRYs up some repetitive parameter declarations
• Switches param names for the outer :ids of coerced queries.

The latter are now named to refer to the outer table: :obs_ids or :desc_ids, to keep them distinct from the :ids param for the inner table.

For example, when coercing from Observation to ImageWithObservations, the param named :ids is converted to :obs_ids to allow it to be handled differently from the param that should mean a set of image :ids.

[coveralls]

Changes unknown
when pulling 817eb80 on standardize-controller-indexes
into ** on main**.