Add unit tests for Smart Router scoring algorithm

[depadeto]

Context

The Smart Router (control-plane/smart-router/main.go) uses a 4-signal scoring algorithm (KV cache, session affinity, load, latency) to pick the best cluster for each request.

Task

Add Go unit tests for the scoreCluster() function covering:

• Cache hit vs miss scoring
• Session pinned vs unpinned
• Different load ratios (0%, 50%, 100%)
• Latency scoring edge cases
• Combined scoring with different weights

Files

• control-plane/smart-router/main.go — the code to test
• Create control-plane/smart-router/main_test.go

Getting started

cd control-plane/smart-router
go test -v ./...

Good first issue — straightforward Go testing, no infrastructure needed.