[Backend] Enhance NestJS Health Check Logic `/health`

[Olowodarey]

Background & Context: The existing RpcClientWrapper gives robust fallback, but overall application health integrates database accessibility and specific lag processing boundaries mapped dynamically.
Description: Subclass @nestjs/terminus (Health Module) adding deep introspection testing explicitly ensuring full stack operability actively constantly mapping.
Acceptance Criteria:

• Create Custom TypeORM TypeOrmHealthIndicator assuring query access passes locally explicitly within ~200ms dynamically mapped bounds.
• Check indexer.service.ts actively resolving validating it has processed a ledger distinctly within the last 15 seconds ensuring no background task halting mathematically.
• Respond natively passing comprehensive object mappings directly to uptime integrations (e.g. Datadog or UptimeRobot) orchestrating 503 fallback routing dynamically natively.
  Target Files: backend/src/modules/health/health.controller.ts.

[blessme247]

@blessme247 has applied to work on this issue as part of the Stellar Wave Program's 3rd wave.

I would like to work on this

ℹ️ Repo Maintainers: To accept this application, review their application or assign @blessme247 to this issue.

[OsagieCynthia]

@OsagieCynthia has applied to work on this issue as part of the Stellar Wave Program's 3rd wave.

I will love to work on this issue please assign

ℹ️ Repo Maintainers: To accept this application, review their application or assign @OsagieCynthia to this issue.