perf: EventEmitter methods on one shared prototype with node's _events store (Refs #10508)

[proggeramlug]

Refs #10508. EventEmitter subclass instances no longer own their methods: they inherit from one shared EventEmitter.prototype, and listener state uses node's _events store.

Why it was per-instance (#6316). super() stamped 15 closures onto every instance, which shadowed a subclass's emit() override, so #6316 hid overridden base methods under a private key. With a real prototype chain the override wins naturally. super.m() walks the chain to the native method and checks it is the native one.

What changed

• super(opts) and EventEmitter.call(this, opts) behave like node's EventEmitter.init: own _events, _eventsCount, _maxListeners, plus captureRejections.
• EventEmitter.prototype gets node's defaults and its methods in node's order, with addListener === on and off === removeListener.
• Listeners are stored node's way (one function or an array per event); once wrappers carry .listener.
• captureRejections now works for subclasses. Rejections go to Symbol.for('nodejs.rejection') or to emit('error'); a non-boolean option throws ERR_INVALID_ARG_TYPE.

Instructions (n=5)

Case	before	this PR
new of an EventEmitter subclass	151.3k	77.1k (−49%)
RSS of the new loop	108 MB	47 MB
emit_ee	51.1k	34.2k (−33%)
commander parse_argv	13.39G	10.43G (−22.1%)
tsc / Zod	–	flat; full collections equal; output matches node

Tests

• Two new gap tests (ESM and CJS) match node 26.5.1 byte-for-byte: own keys and names, hasOwnProperty('on'), overrides with super, seven heritage forms, util.inherits, EventEmitter.call(this), Object.create, mixins, the listener API, errors, captureRejections, and a 3000-emitter loop under moving GC.
• Both new tests fail on the base build, and a sabotage that puts one method back per instance turns both red.
• runtime 4823/0. The node-suite events (70) and stream (802) tests have the same failures before and after.

Not done

• Plain new EventEmitter() is still a handle, so its Object.keys is [] where node prints the three state keys; that needs a separate port.
• Inherited q.emit lookup costs ~24k of emit_ee (method-call follow-up).
• Key order puts birth-layout fields first (class templates, Fresh class objects: extends the evaluated class, own their members, stringify to source (part of #11759) #11780).
• Stream classes and EventEmitterAsyncResource still install their methods per instance.

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📥 Commits

Reviewing files that changed from the base of the PR and between 34acf64 and 9ab2ac6.

⛔ Files ignored due to path filters (1)

• crates/perry-codegen/src/wasm32/runtime_abi.tsv is excluded by !**/*.tsv

📒 Files selected for processing (17)

• changelog.d/PENDING-eventemitter-shared-prototype.md
• crates/perry-codegen/src/expr/this_super_call.rs
• crates/perry-codegen/src/expr/write_barrier.rs
• crates/perry-codegen/src/lower_call/new_helpers.rs
• crates/perry-codegen/src/runtime_decls/stdlib_ffi/streams_events.rs
• crates/perry-runtime/src/closure/dispatch/value_call.rs
• crates/perry-runtime/src/node_stream.rs
• crates/perry-runtime/src/node_stream_constructors/builders.rs
• crates/perry-runtime/src/node_stream_dispatch.rs
• crates/perry-runtime/src/node_stream_event_emitter.rs
• crates/perry-runtime/src/node_stream_keys.rs
• crates/perry-runtime/src/node_stream_readwrite.rs
• crates/perry-runtime/src/object/class_registry/prototype_objects.rs
• crates/perry-runtime/src/object/field_get_set/enumeration.rs
• crates/perry-runtime/src/object/native_module.rs
• test-files/test_gap_eventemitter_shared_prototype.ts
• test-files/test_gap_eventemitter_shared_prototype_cjs.cts

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