Add vector-go-sdk dependency to go.mod

[infraax]

Task: Wire in the vector-go-sdk

Parent epic: #4 (M1 — Robot Connection)
Blocks: All other M1 tasks — nothing can connect without this.

What to do

Add github.com/digital-dream-labs/vector-go-sdk to go.mod and verify it resolves cleanly.

GOMODCACHE=.gomodcache go get github.com/digital-dream-labs/vector-go-sdk
GOMODCACHE=.gomodcache go mod tidy
GOMODCACHE=.gomodcache go build ./...

Verify

• go.mod contains the vector-go-sdk dependency
• go.sum is updated
• make build passes cleanly
• No import errors

Notes

• Always use GOMODCACHE=.gomodcache — system Go cache has root-owned dirs from WirePod.
• The SDK lives at github.com/digital-dream-labs/vector-go-sdk. Check the WirePod source for the exact import path used there if this doesn't resolve.
• This is a cap: go, size: xs task — should take under an hour.

Definition of done

make build passes with vector-go-sdk in the dependency tree.