feat(php-shim): give ported exceptions PHP's class hierarchy

Ported exceptions were flat structs reached with `downcast_ref`, so
Composer's `catch (\RuntimeException $e)` only matched the exact leaf
type and `get_class($e)` had nothing to report. Each exception now
embeds an instance of the class it extends and travels inside an
`AnyThrowable`; `Catch::catch`/`catch_mut` walk that chain, and
`PhpClass::php_class_name` yields the PHP FQCN.

Dropping the `std::error::Error` impls from the exception types leaves
`AnyThrowable` as the only route into an `anyhow::Error`, so the walk
cannot be bypassed. A `no_exception_downcast` linter catches the
`downcast::<X>()` calls that would now silently answer `None`.

Three sites change behavior as a result: the `TransportException`
exit-code override reaches `MaxFileSizeExceededException`, the
`catch (\LogicException)` in findSimilar() reaches its subclasses, and
rendered exception titles carry the real class name rather than a
guess. `get_class_err()` is no longer a `todo!()`, which re-enables
FilesystemRepositoryTest::testCorruptedRepositoryFile.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

2 files changed, 7 insertions, 14 deletions

diff --git a/crates/shirabe-external-packages/src/symfony/console/formatter/output_formatter.rs b/crates/shirabe-external-packages/src/symfony/console/formatter/output_formatter.rs
index f8a5db4c..a0562aef 100644
--- a/crates/shirabe-external-packages/src/symfony/console/formatter/output_formatter.rs
+++ b/crates/shirabe-external-packages/src/symfony/console/formatter/output_formatter.rs
@@ -253,15 +253,11 @@ impl OutputFormatterInterface for OutputFormatter {
     ) -> anyhow::Result<std::rc::Rc<std::cell::RefCell<Box<dyn OutputFormatterStyleInterface>>>>
     {
         if !self.has_style(name) {
-            return Err(anyhow::anyhow!(InvalidArgumentException(
-                shirabe_php_shim::InvalidArgumentException {
-                    message: format!(
-                        "Undefined style: \"{}\".",
-                        shirabe_php_shim::PhpMixed::String(name.to_string()),
-                    ),
-                    code: 0,
-                },
-            )));
+            return Err(InvalidArgumentException::new(format!(
+                "Undefined style: \"{}\".",
+                shirabe_php_shim::PhpMixed::String(name.to_string()),
+            ))
+            .into());
         }
 
         Ok(std::rc::Rc::clone(
diff --git a/crates/shirabe-external-packages/src/symfony/console/formatter/output_formatter_style_stack.rs b/crates/shirabe-external-packages/src/symfony/console/formatter/output_formatter_style_stack.rs
index 2464c028..acfd8878 100644
--- a/crates/shirabe-external-packages/src/symfony/console/formatter/output_formatter_style_stack.rs
+++ b/crates/shirabe-external-packages/src/symfony/console/formatter/output_formatter_style_stack.rs
@@ -57,11 +57,8 @@ impl OutputFormatterStyleStack {
             }
         }
 
-        Ok(Err(InvalidArgumentException(
-            shirabe_php_shim::InvalidArgumentException {
-                message: "Incorrectly nested style tag found.".to_string(),
-                code: 0,
-            },
+        Ok(Err(InvalidArgumentException::new(
+            "Incorrectly nested style tag found.".to_string(),
         )))
     }