Allow hybrid import to be turned on globally

Currently, if a component version is found in the content catalog, the pages from that component version are not imported, even if they are only in the site manifest. This is done to avoid importing pages that may have been deleted. However, it causes problems for distributed components. When only a portion of the distributed component is present in the content catalog (i.e., the current build), the other pages in the distributed component don't get imported.

Add a configuration option to the extension that allows hybrid import to be turned on. When enabled, every page in the site manifest is imported unless it already exists in the content catalog. For example:

antora:
  extensions:
  - require: '@antora/atlas-extension'
    hybrid: true

Since this feature could interfere with validation by fulfiling a reference to a deleted page, it should be possible to turn it on per component version section. For example:

antora:
  extensions:
  - require: '@antora/atlas-extension'
    hybrid:
    - component-name
    - 1.0@other-component-name

The selection is defined as an array of component version patterns (much like in Antora Assembler).