Add firefly/orchestration: sagas, TCC and durable workflows

[ancongui]

Adds firefly/orchestration: sagas, TCC and durable workflows for LaraFly, modeled on jafly's fireflyframework-orchestration and at parity with PyFly's transactional module.

What ships

• Sagas. Steps are declared with #[Saga] and #[SagaStep(dependsOn, compensate, retry, backoffMs, timeoutMs, idempotencyKey, …)].
  • Steps are organized in topology layers. Steps within a layer run sequentially in declaration order, because PHP is synchronous; layer semantics are preserved.
  • Compensation follows one of five policies (strict-sequential, grouped, retry-with-backoff, circuit-breaker, best-effort), with pluggable error handlers.
  • A compensation that stops partway ends COMPENSATION_FAILED and is dead-lettered.
  • Also included: a SagaBuilder DSL, saga composition with data flow, argument injection (#[Input], #[FromStep], #[Header], #[Variable], #[CorrelationId]), #[StepEvent], completion and error callbacks, and #[ScheduledSaga].
• TCC. Ordered #[TccParticipant]s with try/confirm/cancel methods, per-phase timeouts and retries, and #[FromTry]. A TRY that times out is cancelled. TCC executions can be composed.
• Durable workflows.
  • Steps support dependencies and conditions (Symfony ExpressionLanguage).
  • Waiting: signals, timers, wait-for-all/any, child workflows.
  • Lifecycle: continue-as-new, queries, suspend/resume, search attributes, compensation steps.
  • Workflows run SYNC or ASYNC on a Laravel queue.
  • Due work is resumed by firefly:orchestration:tick, which also runs as a #[Scheduled] task under the DistributedLock port.
  • A poison execution is parked and dead-lettered after firefly.orchestration.workflow.max-resume-attempts, so it cannot hold up the tick.
• Persistence. firefly.orchestration.persistence.provider=memory|cache|database.
  • The database provider uses portable tables and is integration-tested on PostgreSQL, MySQL, MariaDB, SQL Server and SQLite.
  • Each execution is guarded by a per-execution lock.
  • Also: a recovery sweep (report, resume or compensate stale executions), retention cleanup, and a dead-letter queue (memory|database) with retry.
• Operations.
  • Lifecycle and step events go out through firefly/eda, and executions can be started by event-type triggers.
  • Observability: an orchestration actuator endpoint and health component, plus metrics and spans through firefly/observability.
  • Commands: php artisan firefly:orchestration:{list,show,signal,dlq,dlq:retry,tick}.
  • An opt-in REST surface.
  • Topology is validated at boot (cycles, unknown dependencies, missing compensations) and fails fast.

Notes

• Includes origin/main (wave W1). The integration tests use IntegrationDsn and its lanes, so they run in the new CI matrix.
• SQL Server fix: the search-attribute upsert ran as a table-scanning MERGE, which blocked on other workers' uncommitted rows. It now writes by exact primary key.

Verification

Run	Result
composer check	exit 0, 6255 passed
Integration on PostgreSQL 16, MySQL 8.4, MariaDB 11 and SQLite	190 passed, 0 failed
SQL Server lane (local, Azure SQL Edge)	60 passed, 0 failed