Request correlation

[Dijjy7]

Observable Request Correlation — Implementation Complete

What was built

New files:

• src/common/correlation/correlation-context.service.ts — AsyncLocalStorage-backed service that propagates a correlation ID across all async contexts (HTTP, queue, DB)
• src/common/correlation/correlation-context.module.ts — @Global() module so every service can inject it

Modified files (15 total, +342 / -79 lines):

Layer | File | Change -- | -- | -- HTTP Middleware | correlation-id.middleware.ts | Now populates AsyncLocalStorage in addition to req.correlationId and response headers App Wiring | app.module.ts, main.ts | Imports CorrelationContextModule; passes service to LoggingInterceptor Logging | logging.interceptor.ts | Reads correlation ID from AsyncLocalStorage as fallback Metrics | metrics.interceptor.ts | Emits structured JSON logs with correlationId, event, status_code, duration_ms on every HTTP request External Calls | trace-external-call.decorator.ts | Resolves correlation ID from AsyncLocalStorage first, then instance property Job Types | job.types.ts | Added `correlationId?: string Job Persistence | job.repository.ts | Stores/retrieves correlation_id column in Supabase jobs table Job Enqueue | job-queue.service.ts | Captures caller's correlation ID from AsyncLocalStorage on every enqueue/enqueueDelayed call Job Execution | job-executor.service.ts | Restores correlation ID into AsyncLocalStorage via correlationContext.run() before handler execution; all downstream calls inherit it Tests | job-queue.service.unit.spec.ts, job-executor.service.unit.spec.ts | Updated with CorrelationContextService mocks Docs | README.md | New "Request Correlation & Distributed Tracing" section explaining end-to-end tracing

Verification results:

• TypeScript: Zero new type errors in production code
• Tests: All 59 tests across 4 affected suites pass — no regressions

closes #563

[MaryammAli]

LGTM