This commit improves how the build deals with javadoc invalid references
in two ways.
Link/see references that are temporarily invalid during javadoc
generation of individual modules are better masked by using the option
`Xdoclint:syntax` instead of `Xdoclint:none` (warnings were still
visible in some cases, e.g. when individually building the javadoc for
a specific module).
Global javadoc-building task `api` now combines `syntax` and `reference`
`Xdoclint` groups, allowing to raise truly invalid references even when
all the modules have been aggregated.
This commit also fixes the 20+ errors which appeared following the later
change in doclet configuration.
Closes gh-30428
This commit reorganizes the asciidoctor attributes for the reference
documentation. Instead of being contributed partially by the build and
individual documents, attributes are now shared in common files that are
included in top sections.
This commit configures the documentation build to merge the entire
reference documentation into a single PDF file.
To achieve that, this commit also fixes duplicate anchors that were
introduced while factoring out common parts of the documentation for MVC
and WebFlux.
Closes gh-28451
This commit creates a new "framework-docs" module, which is dedicated to
documentation generation (reference and API docs).
This commit refactors the build configuration and moves the asciidoc
files to a separate location, but does not change the name nor the
nature of published artifacts.
Closes gh-29417