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/console/html_output_formatter.rs b/crates/shirabe/src/console/html_output_formatter.rs
index 4a5583fb..694f8de6 100644
--- a/crates/shirabe/src/console/html_output_formatter.rs
+++ b/crates/shirabe/src/console/html_output_formatter.rs
@@ -1,7 +1,7 @@
 //! ref: composer/src/Composer/Console/HtmlOutputFormatter.php
 
 use indexmap::IndexMap;
-use shirabe_pcre::{CaptureKey, Preg, PregMatches};
+use shirabe_pcre::{Preg, PregMatches};
 use shirabe_symfony_console::formatter::OutputFormatter;
 use shirabe_symfony_console::formatter::OutputFormatterInterface;
 use shirabe_symfony_console::formatter::OutputFormatterStyleInterface;
@@ -73,8 +73,8 @@ impl HtmlOutputFormatter {
     }
 
     fn format_html(&self, matches: &PregMatches) -> String {
-        let codes_str = matches.get(&CaptureKey::ByIndex(1)).unwrap_or("");
-        let content = matches.get(&CaptureKey::ByIndex(2)).unwrap_or("");
+        let codes_str = matches.get(1).unwrap_or("");
+        let content = matches.get(2).unwrap_or("");
         let mut out = String::from("<span style=\"");
 
         for code_str in codes_str.split(';') {