Expose scheduler builder to ECS World

[waynemwashuma]

Objective

Expose the SchedulerBuilder as an application resource to support:

• schedule inspection/debug tooling
• future runtime schedule manipulation
• external schedule analysis systems

Additionally, refactor the scheduling internals to better separate global builder orchestration from per-schedule compilation logic.

Solution

Previously, the SchedulerBuilder existed as a private field inside App:

app.systemBuilder

This made the scheduling pipeline inaccessible to external systems such as:

• inspectors
• editor tooling
• debugging utilities
• runtime schedule mutation systems

It also tightly coupled schedule compilation state to the builder itself.

Changes made

Exposed SchedulerBuilder as a resource

The builder is now registered through CorePlugin. This allows systems and tooling to access the active scheduling state through the ECS world/resource system. The App now delegates scheduling operations through SchedulerBuilder.Instance instead of maintaining a private instance field.

Refactored schedule compilation into ScheduleContext

As part of exposing the builder globally, the internal scheduling logic was refactored to better isolate per-schedule state.

Introduced ScheduleContext which now owns:

• system registration
• group registration
• parent resolution
• cycle detection
• graph expansion
• topology sorting
• ordering resolution

SchedulerBuilder now primarily acts as:

• a registration collector
• a context factory
• a scheduler orchestration layer

Why this approach

Exposing the scheduler builder as a resource enables future tooling and runtime features without requiring direct access to the App internals.

Examples include:

• visual schedule inspectors
• hot-reloading systems
• runtime system injection/removal
• debugging schedule graphs
• editor integrations

The ScheduleContext refactor supports this by ensuring schedule-local state is isolated and easier to reason about independently.

Showcase

N/A

Migration guide

Notes

• No public system registration API changes.
• Existing scheduling semantics are preserved.
• Scheduler internals are now organized around ScheduleContext.

Checklist

• I have updated the documentation accordingly.
• I have added tests to cover my changes.