Feat: Implemented High-Frequency Contract Calls detection

[Chongai-Cli]

Description

Here's what was built:

4 files created, 1 modified:

apps/backend/src/modules/detection/contracts/
├── interfaces/
│ └── spike-detection.interface.ts ←
SpikeDetectionConfig, ContractActivityRecord,
SpikeAlert
├── spike-detection.service.ts ← core
logic
├── spike-detection.module.ts ← NestJS
module
└── spike-detection.service.spec.ts ← 13 unit
tests

apps/backend/src/app.module.ts ←
SpikeDetectionModule registered

How it works:

The service uses a dual rolling window for baseline
comparison — a "current" window and an equally-sized
"previous" window:

|← baseline window →|← current window →|
now - 2×windowMs now - windowMs now

When recordTransaction(address, timestamp) is
called, it compares the current window count against
the baseline:

• Below minBaselineCount (default 5) → no alert
  (suppresses noise during cold start)
• currentCount / baselineCount < multiplierThreshold
  (default 3×) → no alert
• ≥ 3× → medium, ≥ 5× → high, ≥ 10× → critical
  SpikeAlert

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• [ x] New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Related Issues

Fixes #150
Related to #

Changes Made

Testing

• [ x] I have tested these changes locally
• [ x] Tests pass locally (npm run test)
• [ x] Linting passes (npm run lint)
• [ x] Code is formatted (npm run format)
• [x ] TypeScript builds successfully (npm run build)

Checklist

• [x ] My code follows the style guidelines of this project
• [ x] I have performed a self-review of my own code
• [ x] I have commented my code, particularly in hard-to-understand areas
• [ x] I have made corresponding changes to the documentation
• [x ] My changes generate no new warnings or errors
• [ x] I have added tests that prove my fix is effective or that my feature works
• [ x] New and existing unit tests passed with my changes

Screenshots (if applicable)

Additional Context

[mijinummi]

Hello @Chongai-Cli , thank you for your contribution, please kindly fix the git workflow failures? Thanks for your usual cooperation, looking forward to work with you on this project for more issues