Root decorator to apply multiple values

[theoephraim]

Currently when pulling data from an external source, we must wire up individual items one by one. In many cases, you may already have items labeled correctly on the remote storage, and you just want to apply many values at once. This could be for example a .env style blob in a one password field, or having named items in some kind of key-value storage.

Rather than having each plugin have to reimplement this kind of functionality, the plugin should just focus on fetching the data, and then we can use a built-in root decorator to apply the values. This would be a new root decorator, for example @applyValues and it should be able to take data in different formats (at least .env and json for now).

# @applyValues(op("op://..."))                            # default format is probably .env, or it could try to auto-detect
# @applyValues(op("op://..."), format=json)     # but could set it to parse JSON instead
# ---
ITEM1=val # < this value would be overridden if set by @applyValues

The values applied would have more precedence than values within the file.

We could also want a toggle for whether to set values for new keys that dont already exist in the schema or not.

Please suggest alternative names or any other ideas!