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>

1 files changed, 20 insertions, 25 deletions

diff --git a/crates/shirabe/src/installed_versions.rs b/crates/shirabe/src/installed_versions.rs
index ce78f013..6d702413 100644
--- a/crates/shirabe/src/installed_versions.rs
+++ b/crates/shirabe/src/installed_versions.rs
@@ -202,11 +202,10 @@ impl InstalledVersions {
             return Ok(implode(" || ", &ranges));
         }
 
-        Err(OutOfBoundsException {
-            message: format!("Package \"{}\" is not installed", package_name),
-            code: 0,
-        }
-        .into())
+        Err(
+            OutOfBoundsException::new(format!("Package \"{}\" is not installed", package_name))
+                .into(),
+        )
     }
 
     /// @return string|null If the package is being replaced or provided but is not really installed, null will be returned as version, use satisfies or getVersionRanges if you need to know if a given version is present
@@ -229,11 +228,10 @@ impl InstalledVersions {
                 .map(|s| s.to_string()));
         }
 
-        Err(OutOfBoundsException {
-            message: format!("Package \"{}\" is not installed", package_name),
-            code: 0,
-        }
-        .into())
+        Err(
+            OutOfBoundsException::new(format!("Package \"{}\" is not installed", package_name))
+                .into(),
+        )
     }
 
     /// @return string|null If the package is being replaced or provided but is not really installed, null will be returned as version, use satisfies or getVersionRanges if you need to know if a given version is present
@@ -256,11 +254,10 @@ impl InstalledVersions {
                 .map(|s| s.to_string()));
         }
 
-        Err(OutOfBoundsException {
-            message: format!("Package \"{}\" is not installed", package_name),
-            code: 0,
-        }
-        .into())
+        Err(
+            OutOfBoundsException::new(format!("Package \"{}\" is not installed", package_name))
+                .into(),
+        )
     }
 
     /// @return string|null If the package is being replaced or provided but is not really installed, null will be returned as reference
@@ -283,11 +280,10 @@ impl InstalledVersions {
                 .map(|s| s.to_string()));
         }
 
-        Err(OutOfBoundsException {
-            message: format!("Package \"{}\" is not installed", package_name),
-            code: 0,
-        }
-        .into())
+        Err(
+            OutOfBoundsException::new(format!("Package \"{}\" is not installed", package_name))
+                .into(),
+        )
     }
 
     /// @return string|null If the package is being replaced or provided but is not really installed, null will be returned as install path. Packages of type metapackages also have a null install path.
@@ -309,11 +305,10 @@ impl InstalledVersions {
             });
         }
 
-        Err(OutOfBoundsException {
-            message: format!("Package \"{}\" is not installed", package_name),
-            code: 0,
-        }
-        .into())
+        Err(
+            OutOfBoundsException::new(format!("Package \"{}\" is not installed", package_name))
+                .into(),
+        )
     }
 
     pub fn get_root_package() -> IndexMap<String, PhpMixed> {