encoder library

Dart-to-ball encoder — translates ANY valid Dart source code into ball programs.

Uses package:analyzer for parsing (official Dart SDK parser), so every valid Dart file is parsed correctly. The encoder maps ALL Dart constructs to ball primitives:

• Operators → std.add, std.subtract, std.bitwise_and, etc.
• Control flow → std.if, std.for, std.while, std.try, etc.
• Type operations → std.is, std.as, std.null_check, etc.
• Dart constructs → std.cascade, std.spread, std.record, etc. (universal std)
• Classes → DescriptorProto (fields) + FunctionDefinition (methods)
• Lambdas/closures → FunctionDefinition with name = "" (anonymous)
• Everything else → FunctionCall to std module with MessageCreation input

Language-specific metadata (import URIs, class modifiers, etc.) is preserved in google.protobuf.Struct metadata fields for lossless round-tripping.