refactor!: replace build.rs with compile-time macro build steps

BREAKING CHANGE: Replace the `build`/`builds` feature system with
compile-time macro-driven generation. `gen_program!()` now automatically
invokes `build_comp!()` and `build_pathf!()` when the `comp`/`pathf`
features are enabled, eliminating the need for `build.rs` and
`[build-dependencies]` blocks.

This removes the `build` feature, the `mingling::build` module, and all
related build-time API functions. Completion scripts are now written to
`{target_directory}/mingling/` instead of `target/release/`. The
`mingling_cli` uses `build_comp!("mling")` for its custom binary name.

1 files changed, 19 insertions, 0 deletions

diff --git a/mingling_macros/src/build/pathf.rs b/mingling_macros/src/build/pathf.rs
new file mode 100644
index 0000000..788f527
--- /dev/null
+++ b/mingling_macros/src/build/pathf.rs
@@ -0,0 +1,19 @@
+use std::path::PathBuf;
+
+use mingling_pathf::error::MinglingPathfinderError;
+
+/// The directory where pathf's build artifacts are stored for the current
+/// crate: `{target_directory}/mingling/{CARGO_PKG_NAME}`.
+pub fn output_dir() -> Result<PathBuf, MinglingPathfinderError> {
+    Ok(mingling_pathf::build_output_dir()?.join(crate_name()))
+}
+
+/// Runs the pathf type-mapping analysis for the current crate at compile time
+/// (replacing the previous `build.rs` call).
+pub fn analyze_and_build_type_mapping() -> Result<(), MinglingPathfinderError> {
+    mingling_pathf::analyze_and_build_type_mapping()
+}
+
+fn crate_name() -> String {
+    std::env::var("CARGO_PKG_NAME").unwrap_or_default()
+}