feat: publish Dever core with project scaffolding and versioned AI skills

crates/dever-cli/src/api.rs

@@ -0,0 +1,48 @@
+use std::fs::{self, OpenOptions};
+use std::io::{self, Write};
+use std::path::Path;
+use std::process::ExitCode;
+
+use dever_core::hir::Program;
+
+pub(super) fn check_baseline(program: &Program, root: &Path) -> Result<(), String> {
+    let path = root.join("dever.api");
+    let baseline = match fs::read_to_string(&path) {
+        Ok(baseline) => baseline,
+        Err(error) if error.kind() == io::ErrorKind::NotFound => return Ok(()),
+        Err(error) => {
+            return Err(format!(
+                "cannot read API baseline '{}': {error}",
+                path.display()
+            ));
+        }
+    };
+    program
+        .check_api(&baseline)
+        .map_err(|error| format!("{}: {error}", path.display()))
+}
+
+pub(super) fn write(program: &Program, output: Option<&Path>) -> Result<ExitCode, String> {
+    let snapshot = program.api_snapshot();
+    match output {
+        None => io::stdout()
+            .lock()
+            .write_all(snapshot.as_bytes())
+            .map_err(|error| error.to_string())?,
+        Some(path) => {
+            let mut file = OpenOptions::new()
+                .write(true)
+                .create_new(true)
+                .open(path)
+                .map_err(|error| {
+                    format!("cannot create API snapshot '{}': {error}", path.display())
+                })?;
+            file.write_all(snapshot.as_bytes())
+                .and_then(|()| file.sync_all())
+                .map_err(|error| {
+                    format!("cannot write API snapshot '{}': {error}", path.display())
+                })?;
+        }
+    }
+    Ok(ExitCode::SUCCESS)
+}