refactor(php-shim): remove ArrayObject, inline IndexMap into PhpMixed::Object

ArrayObject was only a thin wrapper around IndexMap<String, PhpMixed>
used as an empty-{} vs empty-[] marker and as the assoc=false JSON
object representation; no reference semantics were involved. Inline its
payload directly into PhpMixed::Object and drop the type along with the
now-dead StdClass.

Side effects of the unification:
- ArrayObject::new was todo!(); the config --global / object-typed get
  paths that built PhpMixed::Object(ArrayObject::new(None)) no longer
  panic.
- base_config_command wrote 'config' as PhpMixed::Array(empty), emitting
  [] instead of {}; now matches PHP's new \ArrayObject ({}).
- The dead is::<StdClass>()/is::<ArrayObject>() instanceof checks in
  JsonManipulator are replaced with the faithful as_object() mapping.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/crates/shirabe/src/command/base_config_command.rs b/crates/shirabe/src/command/base_config_command.rs
index 01952f6..4099ea5 100644
--- a/crates/shirabe/src/command/base_config_command.rs
+++ b/crates/shirabe/src/command/base_config_command.rs
@@ -89,7 +89,7 @@ pub trait BaseConfigCommand: BaseCommand {
                 .borrow()
                 .write(PhpMixed::Array({
                     let mut m = IndexMap::new();
-                    m.insert("config".to_string(), PhpMixed::Array(IndexMap::new()));
+                    m.insert("config".to_string(), PhpMixed::Object(IndexMap::new()));
                     m
                 }))?;
             let _ = Silencer::call(|| {