feat: Add project parser for OpenRewrite

[fabapp2]

This PR provides a first implementation of a Project parser to parse Java projects using Maven to OpenRewrite AST.
The AST together with the provided ExecutionContext can then be used to execute OpenRewrite recipes.
To find OpenRewrite recipes, a RewriteRecipeDiscovery component can be used to discover existing recipes, e.g. from the classpath.

@Component
@RequiredArgsConstructor
public class MyTool {

    // The parser is a Spring bean
    private final RewriteProjectParser parser;
    // RecipeDiscovery is a Spring bean
    private final RewriteRecipeDiscovery recipeDiscovery;
    // ProjectScanner is a Spring bean
    private final ProjectScanner projectScanner;

    public RecipeResult runRecipe(Path baseDir, String recipeName) {
        ExecutionContext ctx = new InMemoryExecutionContext();
        List<Resource> resources = projectScanner.scan(baseDir);
        List<SourceFile> ast = parser.parse(baseDir, resources, ctx);
        Xml.Document rootPom = findRootPom(ast);
        recipeDiscovery.discoverFilteredRecipe(rootPom, recipeName)
            .ifPresent(recipe -> recipe.run(new InMemoryLargeSourceSet(ast), ctx));
    }
}

The parser hooks into the Maven execution and provides the AST as it would be created when running the OpenRewrite Maven plugin.

This implementation programmatically starts the Maven goals clean and install and hooks into the execution with a listener providing access to the MavenSession and MavenProject.
These instances are used to call the MavenMojoProjectParser which does the heavy lifting of parsing the MavenProject to OpenRewrite's AST.

This implementation requires file IO. An attempt to use JIMFS was unsuccessful because at multiple places File is used which is not supported by JIMFS.

Replacing the Maven classes that depend on File (ordering the Maven modules in a new BuildFileGraph impl.) would free the parser from access to File allowing the usage of potentially in-memory Resourcess.

In MavenMojoProjectParser:402 the results of a call to MavenParser.parse() are collected into a List<SourceFile>. This is a problem when a pom contains a parser error which will be returned as ParseError which is a SourceFile but can't be casted into Xml.Document and thus a CCE is thrown. From this exception it is impossible to understand which pom had a problem.

The ParsingListener that can be registered is called for each parsed resource. This would not allow a countdown of resources as the total number of resources is unknown.