Inconsistent option `error?` vs `not_found_error?` for `Ash.get()` vs `get? true` in action?

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### Versions

Ash: 3.15

### Operating system

ubuntu

### Current Behavior

I'm not sure it's a bug or by design but I noticed that the options for "don't return an error if no record is found" is different between `Ash.get` vs a read action with `get? true`:

```ex
# Using Ash.get():
Ash.get(SomeResource, error?: false) # <-- here its `error?`

# Using a read action in a resource:
defmodule MyResource do
actions do
read :some_action do
get? true
end
end
end

MyResource.some_action(not_found_error?: false) # <-- here its `not_found_error?`
```

They seem to be doing the same thing, so shouldn't they use the same option?

### Reproduction

_No response_

### Expected Behavior

_No response_

Compare the Ash.get/2 call using error?: false with the read action using get? true and MyResource.some_action/1 using not_found_error?: false. Trace where each option is defined and handled, then check the related tests or documentation if present; done means the equivalent APIs use a consistent option name and their behavior remains covered.

Written by the indexing model from the issue text.