refactor(pcre): hand back the match instead of copying it out

Preg::match4 and Preg::replace_callback gave callers a
PregMatchedGroups: an IndexMap rebuilt from the match with an owned
String per group, plus a second String for a named group's name key.
That is the copy PregMatches shed when it started wrapping
regex::Captures, reinstated one layer up -- and nearly every regex call
in the tree goes through Preg rather than the shim's preg_* directly, so
almost nothing saw the borrow.

PregMatchedGroups existed only to drop the null (unmatched) groups the
old PregMatches held as Option<String> values. PregMatches::get reports
a non-participating group as None on its own, so the two read alike and
the type collapses into it. Call sites still reach groups through
get(&CaptureKey::ByIndex(N)); what changes is that the value arrives as
a &str borrowed from the subject, which the signatures now carry as a
lifetime.

Three places needed the borrow reckoned with rather than a mechanical
rewrite: PhpFileCleaner::clean and Problem::get_messages read their
groups out before mutating what the match borrows, and
Git::get_authentication_failure names the lifetime of its url argument,
which the result borrows instead of self.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

1 files changed, 15 insertions, 4 deletions

diff --git a/crates/shirabe/src/package/loader/root_package_loader.rs b/crates/shirabe/src/package/loader/root_package_loader.rs
index b7216c62..1d068ad6 100644
--- a/crates/shirabe/src/package/loader/root_package_loader.rs
+++ b/crates/shirabe/src/package/loader/root_package_loader.rs
@@ -256,8 +256,14 @@ impl RootPackageLoader {
                 php_regex!(r"{(?:^|\| *|, *)([^,\s#|]+)(?:#[^ ]+)? +as +([^,\s|]+)(?:$| *\|| *,)}"),
                 req_version,
             ) {
-                let m1 = m.get(&CaptureKey::ByIndex(1)).cloned().unwrap_or_default();
-                let m2 = m.get(&CaptureKey::ByIndex(2)).cloned().unwrap_or_default();
+                let m1 = m
+                    .get(&CaptureKey::ByIndex(1))
+                    .unwrap_or_default()
+                    .to_string();
+                let m2 = m
+                    .get(&CaptureKey::ByIndex(2))
+                    .unwrap_or_default()
+                    .to_string();
                 let mut alias = IndexMap::new();
                 alias.insert("package".to_string(), strtolower(req_name));
                 alias.insert(
@@ -318,7 +324,10 @@ impl RootPackageLoader {
             for constraint in &constraints {
                 if let Some(m) = Preg::is_match3(&pattern, constraint) {
                     let name = strtolower(req_name);
-                    let m1 = m.get(&CaptureKey::ByIndex(1)).cloned().unwrap_or_default();
+                    let m1 = m
+                        .get(&CaptureKey::ByIndex(1))
+                        .unwrap_or_default()
+                        .to_string();
                     let normalized_m1 = VersionParser::normalize_stability(&m1).unwrap_or_default();
                     let stability = stabilities[normalized_m1.as_str()];
 
@@ -368,7 +377,9 @@ impl RootPackageLoader {
                 let name = strtolower(req_name);
                 references.insert(
                     name,
-                    m.get(&CaptureKey::ByIndex(1)).cloned().unwrap_or_default(),
+                    m.get(&CaptureKey::ByIndex(1))
+                        .unwrap_or_default()
+                        .to_string(),
                 );
             }
         }