feat: rewire ingestion stream, configure worker dead-letters, and add trade audit logs

[orunganiekan]

Description

This pull request introduces core data pipelines, resilience primitives, and automated worker loops across the indexer and order management engines inside vatix-backend.

Closes #440
Closes #579
Closes #575
Closes #580

Scope of Changes

1. Real-Time Indexer Ingestion Rewire (#440)

• Deprecated the legacy placeholder ingestFromCursor() loop configuration.
• Successfully injected EventFetcher and PrismaBatchWriter modules into the primary operational PollingIngestionLoop.
• Gated cursor advancement using an explicit batch success flag to ensure storage states never advance ahead of failed database writes.

2. Worker Dead-Letter Resilience Integration (#579)

• Introduced unrecoverable failure interception mechanics within the settlement microservice layers.
• Implemented a low-overhead, durable fallback path routing dead-letter records directly to Redis streams to maintain pipeline continuity without requiring new DB schema tables.

3. Match Engine Audit Logging Streams (#575)

• Re-architected the matching engine execution fill sequences to block on mandatory, awaitable audit callback writes rather than relying on best-effort fire-and-forget logging.

4. Automated Candidate Resolution Systems (#580)

• Wrapped the resolution candidate background evaluator inside a structured background polling daemon featuring overlap protection to safely insulate sequential worker runs.

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Quality Assurance

• Verification: Validated through local repository diff checks and status validation passes to guarantee zero-noise file output.
• History: Sliced cleanly into exactly 4 isolated atomic commits corresponding directly to individual feature requirements.