chore(core): deprecate prefixed accessors/mutators in CommandManager.java
All prefixed (actual) getters/setters in CommandManager have been deprecated, and non-prefixed alternatives have been introduced. I've also put some effort into improving the JavaDocs of these methods.
We now verify the following at compile time:
- That `@CommandMethod` annotated methods are non-static (error)
- That `@CommandMethod` annotated methods are public (warning)
- That the `@CommandMethod` syntax and specified `@Argument`s match
- That no optional argument precedes a required argument
This is the first part of the introduction of annotation processing to cloud. A new `@CommandContainer` annotation has been introduced, which can be placed on classes to have the annotation parser automatically construct & parse the classes when `AnnotationParser.parseContainers()` is invoked.
A future PR will introduce another processor that will scan for `@CommandMethod` annotations and verify the integrity of the annotated methods (visibility, argument annotations, etc.).
This PR also adds a `handler()` getter to the command builder class. This will allow for things along the line of https://github.com/Incendo/cloud/issues/189 to be achieved.
adds a system for processing strings found in annotations before they're used by AnnotationParser
implements #347
Also, because we're using "-Werror", the code won't actually build (and thus tests won't work) using JDK18. To remedy this, a bunch of @SuppressWarnings("serial")s has been added to the exceptions. We don't serialize exceptions, and they're in fact non-serializable because of their members, so this is the appropriate solution (well, the better solution would be to make them serializable, but that's outside the scope of this PR).
