v2.0.0

What's Changed

• Upgraded Go toolchain and module to Go 1.24.6 (from 1.22 / Docker 1.17 images).
• Updated all Dockerfiles to golang:1.24.6-alpine and modernized dependency step (go mod download).

Others

• Added pre-insert uniqueness check for Calls on (name, app_guid).
• Added ScheduleService tests, CallService duplicate-name test adjustment, GenGUID test.
• Added HTTP auth handler tests for GET /calls/:guid (401/404/200 scenarios).
• Fixed vet warning (static error strings now use errors.New).
• Improved Dockerfile package install (apk --no-cache) and removed deprecated go get ./...

Full Changelog: v1.0.3...v2.0.0