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, 8 insertions, 19 deletions

diff --git a/crates/shirabe-class-map-generator/src/class_map_generator.rs b/crates/shirabe-class-map-generator/src/class_map_generator.rs
index 5b745b80..0ee9d992 100644
--- a/crates/shirabe-class-map-generator/src/class_map_generator.rs
+++ b/crates/shirabe-class-map-generator/src/class_map_generator.rs
@@ -3,7 +3,7 @@
 use crate::class_map::ClassMap;
 use crate::file_list::FileList;
 use crate::php_file_parser::PhpFileParser;
-use shirabe_pcre::{CaptureKey, Preg};
+use shirabe_pcre::Preg;
 use shirabe_php_shim::{
     InvalidArgumentException, LogicException, PATHINFO_EXTENSION, RuntimeException, explode,
     getcwd, implode, is_dir, is_file, pathinfo, php_regex, preg_quote, realpath, str_replace,
@@ -351,10 +351,7 @@ impl ClassMapGenerator {
             php_regex!(r"{^( [0-9a-z]{2,}+: (?: // (?: [a-z]: )? )? | [a-z]: )}ix"),
             &path,
         ) {
-            prefix = r#match
-                .get(&CaptureKey::ByIndex(1))
-                .unwrap_or_default()
-                .to_string();
+            prefix = r#match.get(1).unwrap_or_default().to_string();
             path = substr(&path, strlen(&prefix), None);
         }
 
@@ -377,12 +374,7 @@ impl ClassMapGenerator {
         // ensure c: is normalized to C:
         let prefix = Preg::replace_callback(
             php_regex!(r"{(?:^|://)[a-z]:$}i"),
-            |m| {
-                m.get(&CaptureKey::ByIndex(0))
-                    .unwrap_or_default()
-                    .to_string()
-                    .to_uppercase()
-            },
+            |m| m.get(0).unwrap_or_default().to_string().to_uppercase(),
             &prefix,
         );
 
diff --git a/crates/shirabe-class-map-generator/src/php_file_cleaner.rs b/crates/shirabe-class-map-generator/src/php_file_cleaner.rs
index 8b60b4db..18b051c9 100644
--- a/crates/shirabe-class-map-generator/src/php_file_cleaner.rs
+++ b/crates/shirabe-class-map-generator/src/php_file_cleaner.rs
@@ -1,7 +1,7 @@
 //! ref: composer/vendor/composer/class-map-generator/src/PhpFileCleaner.php
 
 use indexmap::IndexMap;
-use shirabe_pcre::{CaptureKey, Preg, PregMatches};
+use shirabe_pcre::{Preg, PregMatches};
 use std::sync::Mutex;
 
 #[derive(Debug, Clone)]
@@ -106,14 +106,14 @@ impl PhpFileCleaner {
                         r#"{<<<[ \t]*(?:"([a-zA-Z_\x80-\xff][a-zA-Z0-9_\x80-\xff]*)"|'([a-zA-Z_\x80-\xff][a-zA-Z0-9_\x80-\xff]*)'|([a-zA-Z_\x80-\xff][a-zA-Z0-9_\x80-\xff]*))(?:\r\n|\n|\r)}A"#,
                     ) {
                         let matched_len = r#match
-                            .get(&CaptureKey::ByIndex(0))
+                            .get(0)
                             .map(|s| s.len())
                             .unwrap_or(0);
                         let delimiter = [1, 2, 3]
                             .iter()
                             .find_map(|i| {
                                 r#match
-                                    .get(&CaptureKey::ByIndex(*i))
+                                    .get(*i)
                                     .filter(|s| !s.is_empty())
                                     .map(str::to_string)
                             })
@@ -149,7 +149,7 @@ impl PhpFileCleaner {
                             if let Some(r#match) =
                                 Preg::is_match4(&entry.pattern, &self.contents, offset)
                             {
-                                return clean + r#match.get(&CaptureKey::ByIndex(0)).unwrap_or("");
+                                return clean + r#match.get(0).unwrap_or("");
                             }
                         }
                     }
@@ -159,10 +159,7 @@ impl PhpFileCleaner {
                 let rest_pattern = REST_PATTERN.lock().unwrap().clone();
                 if let Some(rest_pattern) = rest_pattern {
                     if let Some(r#match) = self.r#match(&rest_pattern) {
-                        let m0 = r#match
-                            .get(&CaptureKey::ByIndex(0))
-                            .unwrap_or_default()
-                            .to_string();
+                        let m0 = r#match.get(0).unwrap_or_default().to_string();
                         clean.push(char);
                         clean.push_str(&m0);
                         self.index += m0.len();