WIP: wrap-java: print failed-to-import methods and include errors in docc

[ktoso]

Not complete yet -- needed a break from other things and this seemed fun to do.

This way users of a library still get a decl and can figure out when they need a method "why" it wasn't imported. Rather than just having no clue why a method is "missing".

This would now render a "failed to import" method like this:

  ///
  /// ### Swift-Java import errors
  ///
  /// * Failed to convert parameter 'arg1' type 'Type(javaHolder: JavaKit.JavaObjectHolder) to Swift'
  @available(*, unavailable, message: "swift-java was unable to import this method. See doc comments for import error details.")
  @JavaStaticMethod
  public func probablePrime(_ arg0: Int32, _ arg1: SwiftJavaFailedImportType) -> BigInteger!

resolves #228

[ktoso]

Ok that has silly issues since overloads may become redefinitions

/__w/swift-java/swift-java/Samples/JavaDependencySampleApp/.build/plugins/outputs/javadependencysampleapp/JavaCommonsCSV/destination/SwiftJavaPlugin/generated/CSVFormat.swift:448:13: error: invalid redeclaration of 'setHeader'
446 |   @available(*, unavailable, message: "swift-java was unable to import this method. See doc comments for import error details.")
447 |   @JavaMethod
448 |   open func setHeader(_ arg0: SwiftJavaFailedImportType) -> CSVFormat.Builder!
    |             `- error: invalid redeclaration of 'setHeader'