feat: add withEventsTracking (#231)

[wolfmanfx]

Summary

Adds withEventsTracking() as a DevTools feature and integrates it with withDevtools() so Redux DevTools shows meaningful event names from @ngrx/signals/events instead of the generic "Store Update".

Context

Debugging SignalStore reducers triggered by @ngrx/signals/events was difficult because DevTools labeled all updates as "Store Update". This resolves the request in #231 by inferring event names and surfacing them to DevTools.
Reference: #231 (comment)

Changes

• Introduce withEventsTracking() as a DevTools feature:
  • Implemented via createDevtoolsFeature({ eventsTracking: true }).
• Extend DevTools internal options:
  • DevtoolsOptions gains eventsTracking?: boolean.
  • DevtoolsInnerOptions gains eventsTracking: boolean.
• Integrate with withDevtools():
  • When eventsTracking is enabled, subscribe to Events.on() via an internal rxMethod.
  • Push event type values into currentActionNames to be used as the next DevTools action label.
• Keep existing DevTools behavior unchanged when the feature is not enabled.

Usage

export const BookStore = signalStore(
  withDevtools('book-store', withEventsTracking()),
  withState({ /* state */ }),
  withReducer(
    on(bookEvents.loadBooks, /* reducer */),
    on(bookEvents.bookSelected, /* reducer */),
  )
);

Compatibility

• Angular 20+: Supported on main.
• Backportable: Compatible with Angular 15–19 (no Angular 20+ only APIs used).
• Breaking changes: None (opt‑in feature).

Testing

• DevTools timeline now displays event names when using withEventsTracking().
• No behavior changes for non‑opt‑in users.

Suggested commands:

pnpm install
pnpm -w lint
pnpm -w test
pnpm -w build

Documentation

• Add a short section under DevTools docs showing withEventsTracking() usage and expectations.

Checklist

• Conventional Commit title with monorepo scope
• Public API unchanged for existing consumers; feature is opt‑in
• No unintended exports
• TypeScript strictness preserved

Linked Issues

Closes #231