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, 2 insertions, 2 deletions

diff --git a/crates/shirabe/src/command/fund_command.rs b/crates/shirabe/src/command/fund_command.rs
index 22c94539..f900bce0 100644
--- a/crates/shirabe/src/command/fund_command.rs
+++ b/crates/shirabe/src/command/fund_command.rs
@@ -10,7 +10,7 @@ use crate::package::base_package::{self};
 use crate::repository::CompositeRepository;
 use crate::repository::RepositoryInterface;
 use indexmap::IndexMap;
-use shirabe_pcre::{CaptureKey, Preg};
+use shirabe_pcre::Preg;
 use shirabe_php_shim::{PhpMixed, impl_php_class, php_regex};
 use shirabe_semver::constraint::AnyConstraint;
 use shirabe_semver::constraint::MatchAllConstraint;
@@ -65,7 +65,7 @@ impl FundCommand {
             if r#type == "github"
                 && let Some(matches) =
                     Preg::is_match3(php_regex!(r"{^https://github.com/([^/]+)$}"), &url)
-                && let Some(sponsor) = matches.get(&CaptureKey::ByIndex(1)).map(str::to_string)
+                && let Some(sponsor) = matches.get(1).map(str::to_string)
             {
                 url = format!("https://github.com/sponsors/{}", sponsor);
             }