macros Reintroduce `r_print!` and `r_println!` macros as public exports, now supporting both explicit buffer argument and implicit `#[buffer]` attr. Add `#[buffer]` attribute macro that wraps unit-returning functions to produce a `RenderResult` with an automatically injected buffer variable. Relax `RenderResult::print()` and `println()` to accept `impl AsRef<str>`.
Refactor #[chain], #[renderer], #[help], and #[completion] macros to keep the original user function as a named item instead of inlining its body. Trait method implementations now call the original function by name, injecting resources from the application context. This improves debugging (stack traces reference user function names), error messages, and macro expansion clarity.
Move routing methods exclusively to the `Routable` trait and update all macro-generated code to reference `Routable` instead of `Grouped`
Restructure flat module layout into logical directories (attr/, derive/, func/, systems/, extensions/, utils.rs). Tighten internal function visibility to pub(crate). All public API signatures remain unchanged.
Implement an `extensions` module in `mingling_macros` that allows attribute macros to accept extension identifiers (e.g., `routeify`) which are re-dispatched as outer attributes before the core macro logic runs, enabling extensibility without modifying existing macros
Add `Routable` implementation for `ChainProcess<ThisProgram>` to enable direct routing of chain process values through the `route!` macro without double-wrapping, improving semantics and flexibility of error conversion
API Refactor six setup types into `mingling::setups::picker` to use chained `PickerArg<Flag>` parsing, replacing direct `global_argument` access. Add `get_args_mut`, `take_args`, and `replace_args` to `Program` for enhanced argument control. These changes are gated behind the `picker` feature, with legacy implementations preserved when the feature is off.