refactor(preg): split PregMatches reads into get() and name()

PregMatches keyed both forms of a capture group through CaptureKey, so
every read built one: a usize wrapped in an enum, or worse, a String
allocated to name a group that regex::Captures can look up from a &str.
It now mirrors regex::Captures instead -- get() takes the group number,
name() the group name -- and the enum drops out of the type entirely.

That is 285 call sites across 59 files, and the named ones carry most of
the win: `matches.get(&CaptureKey::ByName("host".to_string()))` reads as
`matches.name("host")`. ProcessExecutor loses a `user_key` binding that
existed only to build the key once.

CaptureKey stays as the key type of PregMatchesAll and
PregMatchesAllWithOffsets, where numbered and named entries share one
IndexMap and a key type is the point. Five files still name it.

Also retargets the two preg_match_all comments that described the
occurrence count through `matches[&CaptureKey::ByIndex(0)].len()`, an
Index impl these types no longer carry.

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

2 files changed, 13 insertions, 29 deletions

diff --git a/crates/shirabe/src/json/json_file.rs b/crates/shirabe/src/json/json_file.rs
index 2d1185e8..004645c5 100644
--- a/crates/shirabe/src/json/json_file.rs
+++ b/crates/shirabe/src/json/json_file.rs
@@ -8,7 +8,7 @@ use crate::json::JsonValidationException;
 use crate::util::Filesystem;
 use crate::util::HttpDownloader;
 use crate::util::Silencer;
-use shirabe_pcre::{CaptureKey, Preg};
+use shirabe_pcre::Preg;
 use shirabe_php_shim::Catch as _;
 use shirabe_php_shim::{
     InvalidArgumentException, JSON_PRETTY_PRINT, JSON_UNESCAPED_SLASHES, JSON_UNESCAPED_UNICODE,
@@ -451,7 +451,7 @@ impl JsonFile {
             return Ok(Preg::replace_callback(
                 php_regex!(r"#^ {4,}#m"),
                 move |m: &shirabe_pcre::PregMatches| -> String {
-                    let whole = m.get(&shirabe_pcre::CaptureKey::ByIndex(0)).unwrap_or("");
+                    let whole = m.get(0).unwrap_or("");
                     str_repeat(&indent_owned, (strlen(whole) / 4) as usize)
                 },
                 &json,
@@ -552,10 +552,7 @@ impl JsonFile {
 
     pub fn detect_indenting(json: Option<&str>) -> String {
         if let Some(m) = Preg::is_match3(php_regex!(r##"#^([ \t]+)"#m"##), json.unwrap_or("")) {
-            return m
-                .get(&CaptureKey::ByIndex(1))
-                .unwrap_or_default()
-                .to_string();
+            return m.get(1).unwrap_or_default().to_string();
         }
 
         Self::INDENT_DEFAULT.to_string()
diff --git a/crates/shirabe/src/json/json_manipulator.rs b/crates/shirabe/src/json/json_manipulator.rs
index 0f0d50de..9fa8e1e0 100644
--- a/crates/shirabe/src/json/json_manipulator.rs
+++ b/crates/shirabe/src/json/json_manipulator.rs
@@ -4,7 +4,7 @@ use crate::json::JsonFile;
 use crate::json::json_grammar::{self, ValueKind};
 use crate::repository::PlatformRepository;
 use indexmap::IndexMap;
-use shirabe_pcre::{CaptureKey, Preg};
+use shirabe_pcre::Preg;
 use shirabe_php_shim::{
     InvalidArgumentException, LogicException, PhpMixed, addcslashes, array_key_exists, array_keys,
     array_reverse, empty, explode, implode, in_array_loose, is_array, is_int, is_numeric,
@@ -115,10 +115,7 @@ impl JsonManipulator {
             if let Some(groups) =
                 Preg::is_match3(php_regex!("#^\\s*\\{\\s*\\S+.*?(\\s*\\}\\s*)$#s"), &links)
             {
-                let groups_1 = groups
-                    .get(&CaptureKey::ByIndex(1))
-                    .unwrap_or_default()
-                    .to_string();
+                let groups_1 = groups.get(1).unwrap_or_default().to_string();
                 // link missing but non empty links
                 links = Preg::replace(
                     format!("{{{}$}}", preg_quote(&groups_1, None)),
@@ -744,16 +741,14 @@ impl JsonManipulator {
                 &children,
             ) {
                 let mut whitespace = leading_match
-                    .get(&CaptureKey::ByName("trailingspace".to_string()))
+                    .name("trailingspace")
                     .unwrap_or_default()
                     .to_string();
                 let leading_space = leading_match
-                    .get(&CaptureKey::ByName("leadingspace".to_string()))
+                    .name("leadingspace")
                     .unwrap_or_default()
                     .to_string();
-                let content_present = leading_match
-                    .get(&CaptureKey::ByName("content".to_string()))
-                    .is_some();
+                let content_present = leading_match.name("content").is_some();
                 if content_present {
                     let mut value_local = value;
                     if let Some(ref sub) = sub_name {
@@ -942,9 +937,7 @@ impl JsonManipulator {
         if let Some(empty_match) = Preg::is_match3(
             php_regex!("#^\\{\\s*?(?P<content>\\S+.*?)?(?P<trailingspace>\\s*)\\}$#s"),
             &children_clean,
-        ) && empty_match
-            .get(&CaptureKey::ByName("content".to_string()))
-            .is_none()
+        ) && empty_match.name("content").is_none()
         {
             self.contents = format!(
                 "{}{{{}{}}}{}",
@@ -1043,11 +1036,11 @@ impl JsonManipulator {
             &children,
         ) {
             let leading_whitespace = leading_match
-                .get(&CaptureKey::ByName("leadingspace".to_string()))
+                .name("leadingspace")
                 .unwrap_or_default()
                 .to_string();
             let mut whitespace = leading_match
-                .get(&CaptureKey::ByName("trailingspace".to_string()))
+                .name("trailingspace")
                 .unwrap_or_default()
                 .to_string();
             let mut leading_item_whitespace =
@@ -1062,10 +1055,7 @@ impl JsonManipulator {
                 item_depth = 0;
             }
 
-            if leading_match
-                .get(&CaptureKey::ByName("content".to_string()))
-                .is_some()
-            {
+            if leading_match.name("content").is_some() {
                 // child missing but non empty children
                 if append {
                     children = Preg::replace(
@@ -1330,10 +1320,7 @@ impl JsonManipulator {
         // append at the end of the file and keep whitespace
         if let Some(tail_match) = Preg::is_match3(php_regex!("#[^{\\s](\\s*)\\}$#"), &self.contents)
         {
-            let tail_match_1 = tail_match
-                .get(&CaptureKey::ByIndex(1))
-                .unwrap_or_default()
-                .to_string();
+            let tail_match_1 = tail_match.get(1).unwrap_or_default().to_string();
             self.contents = Preg::replace(
                 format!("#{}\\}}$#", tail_match_1),
                 &addcslashes(