feat(api): fluxora database backups and restore runbook (#52)

[Sam-Rytech]

Closes #12, Closes #14, Closes #15, Closes #52

• Durable Storage: Migrated stream state to PostgreSQL with B-Tree indexes for $O(\log N)$ query performance on sender and recipient patterns (GET /api/streams/:id backed by database #15, Indexes: recipient and sender query patterns #12).
• Advanced Discovery: Implemented GET /api/streams filtering by status, sender, and recipient with cursor-based pagination (GET /api/streams filters: status, recipient, sender #14).
• Operational Safety: Added automated DB backup/restore utilities and schema initialization with transaction-safe rollbacks (Database backups and restore runbook #52).
• System Stability: Resolved critical ESM module mocking conflicts and enforced TypeScript strict-mode compliance across the middleware and route layers.

[drips-wave]

@Sam-Rytech Great news! 🎉 Based on an automated assessment of this PR, the linked Wave issue(s) no longer count against your application limits.

You can now already apply to more issues while waiting for a review of this PR. Keep up the great work! 🚀

Learn more about application limits

[Sam-Rytech]

@Jagadeeshftw PR opened

[Sam-Rytech]

@Jagadeeshftw PR awaiting review

[Jagadeeshftw]

@Sam-Rytech Please resolve the conflicts

[Sam-Rytech]

@Jagadeeshftw Conflict resolved

[Sam-Rytech]

@Jagadeeshftw Your attention is needed here

[Sam-Rytech]

@Jagadeeshftw Review needed