Replace all uses of the `new` reserved word with explicit `this new()` constructor definitions and `ClassName.new()` instantiation calls in builtin/core.wren. Update all documentation files (classes.markdown, fiber.markdown, fn.markdown, sequence.markdown, error-handling.markdown, expressions.markdown, fibers.markdown, functions.markdown) to reflect the new constructor syntax, removing `new` keyword examples and replacing them with `ClassName.new()` patterns and `this new()` definitions.
- Compile empty `()` as a valid method signature distinct from no parentheses
- Update `call()`, `clear()`, `run()`, `try()`, and `yield()` to use empty argument lists
- Revise documentation across multiple files to reflect new signature semantics
Add `^category` front matter to branching, classes, error-handling, fibers, functions, lists, looping, maps, method-calls, performance, and qa markdown files. Create new placeholder pages for contributing, core-libraries, and embedding-api under reference category. Remove old embedding and getting-involved pages. Change all `:::wren` code block annotations to `:::dart` across multiple documentation files. Update index title from "Welcome" to "Welcome!" and fix a typo in the Wren class example string. Refine performance page wording for clarity.
Add `^category` front matter to all language, types, and reference doc pages for site navigation restructuring. Replace `:::wren` and `:::java` code block annotations with `:::dart` across multiple files. Create new stub pages for core-libraries, embedding-api, and contributing under the reference category. Remove the old embedding and getting-involved stub pages.
