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, 4 insertions, 10 deletions

diff --git a/crates/shirabe/src/repository/vcs/git_driver.rs b/crates/shirabe/src/repository/vcs/git_driver.rs
index bd56766b..c224e8e6 100644
--- a/crates/shirabe/src/repository/vcs/git_driver.rs
+++ b/crates/shirabe/src/repository/vcs/git_driver.rs
@@ -14,7 +14,7 @@ use crate::util::Url;
 use chrono::TimeZone;
 use chrono::{DateTime, FixedOffset, Utc};
 use indexmap::IndexMap;
-use shirabe_pcre::{CaptureKey, Preg};
+use shirabe_pcre::Preg;
 use shirabe_php_shim::Catch as _;
 use shirabe_php_shim::{
     InvalidArgumentException, RuntimeException, dirname, is_dir, is_writable, realpath,
@@ -200,7 +200,7 @@ impl GitDriver {
                 for branch in &branches {
                     if !branch.is_empty()
                         && let Some(caps) = Preg::match3(php_regex!(r"{^\* +(\S+)}"), branch)
-                        && let Some(name) = caps.get(&CaptureKey::ByIndex(1))
+                        && let Some(name) = caps.get(1)
                     {
                         self.root_identifier = Some(name.to_string());
                         break;
@@ -313,10 +313,7 @@ impl GitDriver {
                         php_regex!(r"{^([a-f0-9]{40}) refs/tags/(\S+?)(\^\{\})?$}"),
                         &tag,
                     )
-                    && let (Some(hash), Some(name)) = (
-                        caps.get(&CaptureKey::ByIndex(1)),
-                        caps.get(&CaptureKey::ByIndex(2)),
-                    )
+                    && let (Some(hash), Some(name)) = (caps.get(1), caps.get(2))
                 {
                     self.tags
                         .as_mut()
@@ -352,10 +349,7 @@ impl GitDriver {
                         php_regex!(r"{^(?:\* )? *(\S+) *([a-f0-9]+)(?: .*)?$}"),
                         &branch,
                     )
-                    && let (Some(name), Some(hash)) = (
-                        caps.get(&CaptureKey::ByIndex(1)),
-                        caps.get(&CaptureKey::ByIndex(2)),
-                    )
+                    && let (Some(name), Some(hash)) = (caps.get(1), caps.get(2))
                     && !name.starts_with('-')
                 {
                     branches.insert(name.to_string(), hash.to_string());