feat(picker): add core trait, types, and builder macro for argument

parsing

Implement the foundational `mingling_picker` library along with its
companion
`mingling_picker_macros` crate. The picker provides:

- `Pickable` trait for parsing types from raw strings
- `PickerResult` enum modeling parse outcomes
- `Picker` struct for storing and indexing command-line arguments
- `PickerRequirement` struct for declarative parameter definitions
- `PickerPattern` family (1..32) of typed pattern structs via the
  `internal_repeat` proc macro
- `req!` proc macro as a succinct builder for `PickerRequirement`

Re-export `mingling_picker::macros::*` from the `mingling` crate when
the
`picker` feature is enabled, replacing the previous wildcard re-export
of
`mingling_macros`.

1 files changed, 19 insertions, 1 deletions

diff --git a/mingling_picker/src/lib.rs b/mingling_picker/src/lib.rs
index 3c3251d..97020a4 100644
--- a/mingling_picker/src/lib.rs
+++ b/mingling_picker/src/lib.rs
@@ -1 +1,19 @@
-pub mod prelude {}
+mod picker;
+pub use picker::*;
+
+mod pickable;
+pub use pickable::*;
+
+mod requirement;
+pub use requirement::*;
+
+mod result;
+pub use result::*;
+
+pub mod prelude {
+    pub use crate::IntoPicker;
+}
+
+pub mod macros {
+    pub use mingling_picker_macros::*;
+}