Ability to mark all APIs in submodules deprecated

## :rocket: Feature Request

### Description

There's currently a way to deprecate specific APIs in a module, using the `@deprecated` tag. However, entire submodules need a quick and easy way to be completely deprecated. This is a problem in `aws-cdk` (see `elasticsearch` deprecation).

### Proposed Solution

We probably need a `deprecated` flag in `jsiirc.json` that will mark all APIs in that particular submodule as deprecated. Tentatively agreeing to take this on the next time `aws-cdk` has a submodule that needs deprecation.

Start by reading how jsiirc.json represents module-level configuration and compare it with the existing @deprecated handling for individual APIs. Use the aws-cdk elasticsearch deprecation as the motivating case, then define what the deprecated flag should affect across a submodule and how completion can be verified.

Written by the indexing model from the issue text.