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, 2 insertions, 4 deletions

diff --git a/crates/shirabe/src/util/platform.rs b/crates/shirabe/src/util/platform.rs
index 629854b6..f2b8aea3 100644
--- a/crates/shirabe/src/util/platform.rs
+++ b/crates/shirabe/src/util/platform.rs
@@ -2,7 +2,7 @@
 
 use crate::util::ProcessExecutor;
 use crate::util::Silencer;
-use shirabe_pcre::{Preg, PregMatchedGroups};
+use shirabe_pcre::{Preg, PregMatches};
 use shirabe_php_shim::{
     PHP_ENV, PHP_SERVER, PhpMixed, PhpResource, RuntimeException, defined, file_exists,
     file_get_contents, fstat, function_exists, getcwd, getenv, ini_get, is_readable, mb_strlen,
@@ -98,15 +98,13 @@ impl Platform {
         // two forms are written as an explicit alternation: `$VAR` or `%VAR%`.
         Preg::replace_callback(
             php_regex!(r"#^(?:\$(?P<dvar>\w+)|%(?P<pvar>\w+)%)(?P<path>.*)#"),
-            |matches: &PregMatchedGroups| -> String {
+            |matches: &PregMatches| -> String {
                 let var = matches
                     .get(&CaptureKey::ByName("dvar".to_string()))
                     .or_else(|| matches.get(&CaptureKey::ByName("pvar".to_string())))
-                    .map(|s| s.as_str())
                     .unwrap_or("");
                 let path_part = matches
                     .get(&CaptureKey::ByName("path".to_string()))
-                    .map(|s| s.as_str())
                     .unwrap_or("");
                 // Treat HOME as an alias for USERPROFILE on Windows for legacy reasons
                 if Platform::is_windows() && var == "HOME" {