feat(resolution): bridge Laravel event(new X) to its listener handles

Laravel decouples an event dispatch from its listener(s), linked by the event
class: event(new OrderShipped($order)) has no static edge to the
handle(OrderShipped $event) that runs it (usually a separate app/Listeners/
class). laravelEventEdges bridges each event(new X(...)) site -> every
listener's handle for X.

Two registration mechanisms, both real and both needed (built together):
- (A) auto-discovery: a typed handle(EventType $e) first param, read from the
  method declaration source (PHP method nodes carry no signature, like C#); a
  handle(A|B $e) union is split into two events.
- (B) the `protected $listen = [XEvent::class => [Listener::class, ...]]` map in
  an EventServiceProvider, parsed from comment-stripped source (so a
  fully-commented map on an auto-discovery app contributes nothing). This is the
  only way to link a listener whose handle() is untyped.

Job exclusion is free: queued jobs dispatch via ::dispatch()/dispatch() (not
matched) and their handle() takes an injected service, never an event type, so
matching only event(new X) excludes them by construction. `use Dispatchable` is
not keyed on (unreliable in real apps).

Surfaces as `dynamic: laravel event` via the generic synth-edge fallback.

Validated 100% precision on two grep-confirmed repos exercising both
mechanisms: koel (small, populated $listen map, 9 edges incl. the untyped-handle
case and a fan-out) and firefly-iii (large, pure auto-discovery / empty $listen,
141 edges, 0 source/target false positives, 0 namespace mismatch, union split
verified); 0 on the guzzle control. Namespace-agnostic (FireflyIII\ not
hardcoded). Node-stable (pure edge synth). Suite 1623 green.

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

CHANGELOG.md

@@ -19,6 +19,7 @@ and adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 - `codegraph_explore` now follows **Spring application events** in Java. A `publishEvent(new OrderShippedEvent(...))` call now links to every `@EventListener` that handles that event — usually in a different class — so "what reacts when this is published?" traces from the publisher straight into each listener method instead of dead-ending at `publishEvent(...)`. The link is by event type, and all the common listener styles are recognized: a `@EventListener` typed on its parameter, the `@EventListener(SomeEvent.class)` form, `@TransactionalEventListener`, and the older `implements ApplicationListener<SomeEvent>`. One event fans out to all its listeners, and a plain Spring app with no event bus is unaffected.
 - `codegraph_explore` now follows **MediatR** request and notification dispatch in C#/.NET. A `_mediator.Send(command)` or `_mediator.Publish(notification)` call now links to the `Handle` method of the matching `IRequestHandler<>` / `INotificationHandler<>` — usually in a different file in a Clean Architecture layout — so "what handles this command?" traces from the controller straight into the handler instead of stopping at the mediator call. The sent type is recognized whether it's constructed inline (`Send(new GetFooQuery())`), built into a local first (`var cmd = new …; Send(cmd)`), or passed in as a parameter, and it's matched by type — so a `MessagingCenter.Send(...)` or a same-named DTO that isn't a request is never mislinked, and a project without MediatR is unaffected.
 - `codegraph_explore` now follows **Sidekiq** background-job dispatch in Ruby. A `DestroyUserWorker.perform_async(id)` (or `.perform_in` / `.perform_at`) call now links to that worker's `perform` method — usually in `app/workers/` away from the controller or model that enqueues it — so "what runs in the background here?" traces from the enqueue straight into the job body. Both the modern `include Sidekiq::Job` and the older `Sidekiq::Worker` are recognized, namespaced workers resolve to the right class even when several share a name (e.g. `Comments::NotifyWorker` vs `Articles::NotifyWorker`), and Rails ActiveJob's `perform_later` — a different mechanism — is intentionally left alone.
+- `codegraph_explore` now follows **Laravel events** in PHP. An `event(new OrderShipped($order))` call now links to every listener that handles it — each listener's `handle()` method, usually a separate `app/Listeners/` class — so "what reacts to this event?" traces from the dispatch straight into the listener bodies. Listeners are found both ways Laravel registers them: by a typed `handle(OrderShipped $event)` (auto-discovery, including a `handle(A|B $event)` union that listens for two events) and by the `protected $listen` map in your `EventServiceProvider` (which also catches a listener whose `handle()` has no type-hint). One event fans out to all its listeners, and queued jobs — dispatched via `::dispatch()` rather than `event()` — are correctly left out.
 
 - `codegraph_explore` now surfaces the right code in large multi-layer projects. When you ask a backend-flow question in a repo that pairs an API server with a big frontend that mirrors the same domain words — say an `app/` admin UI sitting over an `api/` server — the server-side file that genuinely matches several of your query's terms is no longer pushed out of the results by the larger, more interconnected frontend layer. A file corroborated by two or more distinct query terms is now kept in the answer even when a denser unrelated layer would otherwise crowd it out, so "how does X read items / handle the request" returns the service or handler that does the work instead of a wall of frontend views. Single-layer projects are unaffected; set `CODEGRAPH_RANK_NO_MULTITERM=1` to revert to the previous ranking.
 - Impact and blast-radius analysis for TypeScript, JavaScript, Go, Python, Rust, Ruby, C, Java, C#, PHP, Scala, Kotlin, Swift, Dart, and Pascal/Delphi now understands the readers of a constant. When you change a file-scope, package-level, module-level, or class-level constant — a config object, a lookup table, a shared constant — the other symbols in that file that read it now show up as affected, where before they were invisible (impact only followed calls, imports, and inheritance, so a constant's consumers looked like "nothing depends on this"). This makes `codegraph impact`, and the impact trail in `codegraph_explore`/`codegraph_node`, catch the "change this table, break its readers" class of change. It's on by default and adds no nodes to your graph; bundled/minified files and ambiguously-shadowed names are skipped to keep results precise. Set `CODEGRAPH_VALUE_REFS=0` to turn it off.