refactor(crates): split metadata-minifier and spdx-licenses into own crates

Move MetadataMinifier and SpdxLicenses out of shirabe-external-packages
into dedicated shirabe-metadata-minifier and shirabe-spdx-licenses
crates, updating all import sites accordingly.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

3 files changed, 52 insertions, 0 deletions

diff --git a/crates/shirabe-metadata-minifier/Cargo.toml b/crates/shirabe-metadata-minifier/Cargo.toml
new file mode 100644
index 0000000..6f11402
--- /dev/null
+++ b/crates/shirabe-metadata-minifier/Cargo.toml
@@ -0,0 +1,11 @@
+[package]
+name = "shirabe-metadata-minifier"
+version.workspace = true
+edition.workspace = true
+
+[dependencies]
+shirabe-php-shim.workspace = true
+indexmap.workspace = true
+
+[lints]
+workspace = true
diff --git a/crates/shirabe-metadata-minifier/src/lib.rs b/crates/shirabe-metadata-minifier/src/lib.rs
new file mode 100644
index 0000000..342786f
--- /dev/null
+++ b/crates/shirabe-metadata-minifier/src/lib.rs
@@ -0,0 +1,3 @@
+mod metadata_minifier;
+
+pub use metadata_minifier::*;
diff --git a/crates/shirabe-metadata-minifier/src/metadata_minifier.rs b/crates/shirabe-metadata-minifier/src/metadata_minifier.rs
new file mode 100644
index 0000000..3f1a4fc
--- /dev/null
+++ b/crates/shirabe-metadata-minifier/src/metadata_minifier.rs
@@ -0,0 +1,38 @@
+//! ref: composer/vendor/composer/metadata-minifier/src/MetadataMinifier.php
+
+use indexmap::IndexMap;
+use shirabe_php_shim::PhpMixed;
+
+#[derive(Debug)]
+pub struct MetadataMinifier;
+
+impl MetadataMinifier {
+    pub fn expand(versions: Vec<IndexMap<String, PhpMixed>>) -> Vec<IndexMap<String, PhpMixed>> {
+        let mut expanded: Vec<IndexMap<String, PhpMixed>> = Vec::new();
+        let mut expanded_version: Option<IndexMap<String, PhpMixed>> = None;
+        for version_data in versions {
+            if expanded_version.as_ref().is_none_or(|ev| ev.is_empty()) {
+                expanded.push(version_data.clone());
+                expanded_version = Some(version_data);
+                continue;
+            }
+
+            // add any changes from the previous version to the expanded one
+            let ev = expanded_version.as_mut().unwrap();
+            for (key, val) in version_data {
+                if matches!(&val, PhpMixed::String(s) if s == "__unset") {
+                    ev.shift_remove(&key);
+                } else {
+                    ev.insert(key, val);
+                }
+            }
+
+            expanded.push(ev.clone());
+        }
+
+        expanded
+    }
+
+    // MetadataMinifier::minify() is not ported because it is not used in Composer itself.
+    // The function is mainly for package repositories.
+}