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, 3 deletions

diff --git a/crates/shirabe/src/cache.rs b/crates/shirabe/src/cache.rs
index 43aed95d..47f3219c 100644
--- a/crates/shirabe/src/cache.rs
+++ b/crates/shirabe/src/cache.rs
@@ -6,7 +6,7 @@ use crate::util::Filesystem;
 use crate::util::Platform;
 use crate::util::Silencer;
 use chrono::Utc;
-use shirabe_pcre::{CaptureKey, Preg};
+use shirabe_pcre::Preg;
 use shirabe_php_shim::{
     ErrorException, bin2hex, clearstatcache, date_format_to_strftime, dirname, disk_free_space,
     file_exists, file_get_contents, file_put_contents, filemtime, function_exists, hash_file,
@@ -205,8 +205,8 @@ impl Cache {
                         let message = format!(
                             "<warning>Writing {} into cache failed after {} of {} bytes written, only {} bytes of free space available</warning>",
                             temp_file_name,
-                            m.get(&CaptureKey::ByIndex(1)).unwrap_or_default(),
-                            m.get(&CaptureKey::ByIndex(2)).unwrap_or_default(),
+                            m.get(1).unwrap_or_default(),
+                            m.get(2).unwrap_or_default(),
                             free_space,
                         );