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>

1 files changed, 3 insertions, 6 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()